Day 0: Hunting, gathering, and assembly of materials

The first challenge was in finding a rectangle that fit inside our fireplace. Actually, we had planned to go with a Fluval 26 Bow, which would nicely fill in the width, but not the height. Then we discovered a 12x24 High tank that fit just perfect. So perfectly that I had to use extra small casters to build the stand that would allow us to slide it in and out for maintenance.

Before I could fill the tank, I had to build a stand to hold it. The catch was that it also needed to be on casters so that it could slide in and out of the fireplace for (hopefully infrequent) tank maintenance. With the 24 hour clock on our aquarium plants ticking away, I sawed and glued and screwed away at the stand.


You can't see here, but in the final version the stand has two more castors in the middle, along with additional brackets to reinforce. Once fully assembled, I sprayed the tank stand down with black semi-gloss Rustoleum paint and went to off to bed while the paint dried. This was the final product.

 

Day 1: Filling and scaping the tank

While the tank stand/dolly contraption was drying, the driftwood I selected was soaking in a cooler immersed in hot-but not-boiling tap water in order to get a head start on leaching out the tannins. By noon the next day the dolly was dry, the driftwood soak was looking surprisingly clear, and the aquarium plants were running out of time. It was time to start building and filling the tank.

Unfortunately, no one at the LFS had any direct experience with dirted, Walstad-style tanks. So a lot of this was cobbled together from YouTube videos, forum posts, and fish store employee knowledge that was tangentially applicable to the kind of tank we were trying to build.

I started by lining the outside edges of the tank bottom with small-diameter Peace River Super Natural Gravel so that the soil wouldn't be visible from the front of the tank. Then I filled in approximately 1 inch of sifted and pre-soaked Miracle Gro Organic Potting Soil. Once that was in, I set the driftwood in place and covered the soil and the base of the driftwood with approximately 2 inches of gravel.

With the 24-hour clock on our aquarium plants running out, I then began arranging hardscape (rocks), gluing plants to them (Java Fern and Anubias Coffeefolia), and inserting rooted Micro Sword and Crypt Bronze Fan plants into the substrate in the foreground.

With that complete, I partially filled the tank with treated water and planted approximately 24 Hygro Angustifolia Fan stems in the background. With that, the tank was ready to be filled the rest of the way up, dialed in for pretty light with a Fluval Plant 3.0 led lamp, and put to bed.

 

That’s a really cool project! I’ll enjoy following along. I do highly recommend doing a minimum of monthly water changes though. It’ll keep the water parameters from being drastically different between the tank and the new water, and just generally give you a healthier tank.

 

Thank you, Kwyet!

Some rookie questions: How much water do you generally change at a time on a low-tech tank? What are the water parameters that are aided by this? I got into this being seduced by the claims of dirt tankers that they've gone years between water changes thanks to plant-based filtration and a low ratio of fish to plants.

 

Days 2-9: Here fishy fishy...

The next morning the plants were still alive, our first water test came back as expected (zero ammonia, zero nitrites, zero nitrates, and a pH of 7.1), and I was feeling excited and impatient. While waiting for the plants' roots to reach the soil, I decided it was time to introduce carbon and nitrogen the old-fashioned way and put some fish in the tank.

Towards the end of day 2 my wife and I ventured back to the LFS and came back with 3 Dwarf Honey Gouramis (1 red, two yellow), some fish food, and some refrigerated Turbostart beneficial bacteria. The fish survived the night, and on day 3 we went back for 6 Blue Endlers.

A water test the morning of day 4 showed some predictable but cautionary signs. Ammonia and nitrites were creeping up, both up at .25ppm, and nitrates had risen to 1ppm. We were off to the races with the Nitrogen Cycle!

Or so I thought.

Still filterless at this point, we also added a small powerhead (the Sicce Voyager Nano which, at 530gph proved way to powerful for our tank and its new inhabitants. That one would need to go back. We eventually settled on an internal filter for generating water movement--the Fluval U1 at 65gph--with the sponge left in place but the Biomax biofilter removed to keep our precious plant nutrients intact. In place of the biofilter I inserted a Chemi-Pure Green Nano packet to keep tannins down and water clarity up.

With the sponge filter/Chemi-Pure in place, we tested our water over the next couple of days and were still seeing some fairly stable readings. Ammonia was creeping up a bit to between .3 and .5ppm, but nitrites were still down around .25ppm and nitrates were rising to 4, then 5, then 7ppm. Seeing the nitrogen cycle taking hold, I felt mostly comfortable leaving the tank for a weekend camping trip, but I thought about the tank constantly while we were away.

Upon our return yesterday we were elated to find all our fish still alive and thriving. However that elation quickly dissipated as a water test showed that our nitrites had shot up to 1.5ppm. I added a 2x dose of water conditioner and headed for the LFS for more technology. This was not going to be an effortless, no water change MD Fish Tank experiment.

I came home with a siphon hose, some Poly Fill, some additional units of beneficial bacteria, and some macro/micro nutrients for our plants (Thrive+ and Excel), which had been grown emmersed and were starting to look a little shabby. The low-tech tank experiment felt like it was falling apart!

​

We performed a ~15% water change last night and added a full dose of water treatment to the new water. Today's (Day 9) test did little to assuage us. While nitrates continue to climb, so do nitrites and ammonia. The employee at the LFS assured us that while the water treatment liquid would protect the fish, the chemical reactions that it would trigger being converted into non-toxic ammonia and nitrites, those new molecules would continue to test positive.

Welcoming all ideas on how we can protect our fish, nurture our plants, and save the dream of the low-tech dirt tank!

 

While it is true that the amount and frequency of water changed depends on your water parameters, you can’t test for everything that would indicate a need for a change. Usually people test for ammonia, nitrite, nitrate, gH, and kH, but the fish are also putting hormones in the water and the water is also absorbing things from the atmosphere such as chemicals from perfumes, cleaning supplies, etc. While the tank may appear healthy and operate seemingly well for a long period of time, you are much less likely to encounter diseases and sudden mysterious die-offs if you are maintaining a regular water change schedule. You can get most of the above in the API Master test kit. You can buy the gH and kH from them as a separate kit. Note that you should use liquid test kits rather than test strips, as the liquid tests are much more accurate.

Currently I do a 20% water change on most of my tanks weekly. There is one that I do every other week because its parameters change very little from week to week. This schedule keeps my measurable parameters at 0 ammonia, 0 nitrite, 10-20 nitrate, 6 dgH, 1-2 dkH. If my nitrates were rising considerably higher than that from a heavier fish load, I’ve done as much as 50% weekly in the past. I’ve also done 50% monthly, but found over time that it didn’t work as well for fish or plants. It just depends how much things change weekly to let you know if you need to do more and larger water changes. However, even if those numbers are staying optimal for months, I guarantee you that other unmeasurable things are building up in your tank and it would benefit from at least monthly water changes.

All of that aside though, my heart sank when I read that you added fish so soon. Frequently bottled bacteria is dead when you buy it, and even if it isn’t it’s not going to do an instant cycle on your tank, or be able to handle a fully stocked tank. Ideally, you want to have fishlessly cycled the tank before adding livestock as described here. I would say to take your fish back to the store or move them to a separate holding container that you can do daily water changes on until you can finish cycling your tank. If you’re not willing to do that, then add Prime and your bacteria daily according to directions. Add Prime up to 5x the dose according to how high the ammonia and nitrite are, for example 1 ppm ammonia plus 2 ppm nitrite would require 3x the Prime dose. If it gets to where you need 5x a dose of Prime, do a 50% water change. Note that you still might get some fish losses with this method and it’s not really known how much discomfort they are experiencing, just that Prime helps to mitigate the effects of the ammonia and nitrite and results in less fish death. It’s best for them not to be in an uncycled tank at all.

Also, please take YouTube and pet store advice with a heaping grain of salt, as often they’re just trying to sell as much as possible or get as many views as possible.

 

Thank you so much for this thoughtful reply, Kwyet. Your compassion and dedication to the wellbeing of the fish lives under your care is obvious. My wife and I share your values and aspire to be as responsible of fish keepers as you are. Obviously we have a long road ahead of us.

I currently have the API Master Kit, and have now ordered a TPM meter as well as indicators for gH and kH. With these I hope to get closer to understanding the non-nitrogen based sources of contaminants. As you can see, our tank is fairly removed from potential sources of airborne contaminants like perfume or cleaning supplies. It has a lid. And we do have an air purifier in the living room where it is situated. But this is the first I'm hearing about fish hormones. Again, a long road ahead of us.

I truly wish I had found this forum, or even better that you had been at the fish store, when we were puzzling over how to get our nitrogen cycle started. I initially went in telling them that I wanted a bottle of ammonia and a bottle of beneficial bacteria to start a plant-only nitrogen cycle weeks before introducing fish. They looked at me like I had three heads. Even though this was the highest quality, dedicated aquarium store in our city, their otherwise very knowledgable staff are not all that familiar with low-tech planted/dirted/Walstad aquariums. As such, they encouraged me to introduce a small bio-load of fish as the source of ammonia to start the nitrogen cycle. For a 30-gallon tank, I think we are still quite low in terms of bio-load, with about 7 inches of Dwarf Gourami and 3 inches of small Blue Endlers. But if I had known that our nitrites were going to spike after introducing the fish I would not have proceeded this way. I now know that some folks use fish food as a non-living source of ammonia to start the nitrogen cycle.

At this point the store will not take the fish back, so we are going to do our best to help them through this period. We are using something equivalent to Prime (it is a chlorine water treatment bottle re-branded by the store, with the usual "1ml per 10 gallons, up to 5x per 24 hours dosage in case of toxic nitrogen" labeling). The problem we encounter now is that this water treatment solution doesn't eliminate the ammonia and nitrites, I am told. It simply changes them to a non-toxic molecular structure. As a result, our tests will still come back with discouraging levels. Unless of course we begin resorting to more dramatic water changes...

We now have the siphon hose and are equipped to do as much water changing as is required. My only hesitation about getting too aggressive with the water changes at this stage is that we are also dosing the tank with beneficial bacteria and trying to establish a good nitrogen cycle. We are running a sponge filter that should help between water changes, but I have no way of knowing how well established the BB are in that sponge.

All of this is to say that I greatly appreciate your time and experience in these matters and would welcome any suggestions you might have for getting our fish through this next stage. For now, I'm happy to report that they appear healthy, with no gasping at the top of the tank for air kind of behavior. Though I do hear you that they may still be experiencing distress.

 

Thank you! In your situation, I wouldn’t trust a no-name dechlorinator. It might be exactly the same as Prime, but I would rather rely on something with proven efficacy. It’s up to you of course. Also, I should mention that these dechlorinators lower the oxygen level in the tank, which is why you may not want to take it to the extreme 5x limit, or you may want to add some extra aeration if you’re approaching that.

One other suggestion is to try to get a filter sponge, filter media and/or some substrate from an already cycled tank from someone in your area (better from a hobbyist than the fish store). I realize that you’re already adding bacteria, but you would know it was alive if it was coming from an established tank. Also, I’ve read that bottled bacteria contains mostly the bacteria that uses ammonia instead of those that convert the nitrites to nitrate, and the nitrite converters take longer to get established. I would think you would get a more balanced mix from an actual tank.

Finally, when you do water changes while working on cycling, keep that sponge filter submerged, the water at roughly the same temp, and it shouldn’t affect the cycling process very much. Do read through that link because it has a lot of information on things that help the beneficial bacteria to grow.

 

Thanks again, Kwyet!

Unfortunately we don't know anyone with an extra sponge right now. That being the case, what percentage water change would you recommend, and with what frequency, while we're waiting for the final bit of nitrite->nitrate conversion to cycle?

 

Fortunately, an astute employee and aquarist pointed out that a heavily planted tank can go as long as 3 months without water changes.

Unfortunately, that's just not based in reality when it comes to planted tanking.

If everything is balanced, the plants are using available nutrients, nutrients are being added back in, water changes are not necessary.

Nope. Not the case. 105 gallons gives you tons more leeway than a 30gal tank.

Here's why water changes are necessary when livestock is involved:

you can’t test for everything that would indicate a need for a change. Usually people test for ammonia, nitrite, nitrate, gH, and kH, but the fish are also putting hormones in the water and the water is also absorbing things from the atmosphere

This is an awesome project and with a little effort, you'll be able to turn it into a showpiece, @donrleonard. Looking forward to following along to see how it develops! Gotta second that recommendation to pick up a bottle of Prime.

With your setup, you're definitely going to need to re-think your water change plans. It's gonna be weekly for a while. Then maybe every other week. I can't imagine ever dropping to monthly unless you have almost nothing in terms of livestock. Water changes don't have to be daunting, though - you could easily use a cheap pump with hose barbs to run flexible tubing into the tank to pump water in and out. I can't remember the last time I did a water change on a tank over 10gal without using a pump to add things back. Maybe the best $20 I've ever spent.

 

Unfortunately, that's just not based in reality when it comes to planted tanking.



Nope. Not the case. 105 gallons gives you tons more leeway than a 30gal tank.

Here's why water changes are necessary when livestock is involved:



This is an awesome project and with a little effort, you'll be able to turn it into a showpiece, @donrleonard. Looking forward to following along to see how it develops! Gotta second that recommendation to pick up a bottle of Prime.

With your setup, you're definitely going to need to re-think your water change plans. It's gonna be weekly for a while. Then maybe every other week. I can't imagine ever dropping to monthly unless you have almost nothing in terms of livestock. Water changes don't have to be daunting, though - you could easily use a cheap pump with hose barbs to run flexible tubing into the tank to pump water in and out. I can't remember the last time I did a water change on a tank over 10gal without using a pump to add things back. Maybe the best $20 I've ever spent.

Thanks for sharing your experience, somewhatshocked! After doing one 15% change last night with a hand pump, the idea of a pump seems positively divine. I've just placed an order for one on Amazon.

I'd like to invite you to help me figure out a water change regimen here also. If your tank is partially cycling but still showing positive levels of ammonia and nitrite, how much water would you change how often at this early stage?

 

OP.

Cool tank, cool thread OP, putting it in the fireplace is a really unique idea.

I am currently cycling a tank using the fish in method, which is essentially what you are doing by mistake. I am doing it on purpose. I have 19 guppy fry in a 5gal planted tank, i dont care if the guppy fry die or not, they'd be food for bigger fish if i hadnt of scooped them out of their tank to use as ammonia in my 5gal that im cycling. It may seem cruel to some, but fry can withstand ammonia much better than adults. They are less than a quarter inch long, may 1 week old.

I am doing a 1gal water change every other day in this tank, so 20% every other day while cycling. Their tiny bodies are not creating enough ammonia to measure on the API test but i know there is some there, no nitrate/nitrite yet.

I would suggest in your 30gal tank to do 10 gal water change every other day to help with the ammonia. 10gal seems easy to age in two 5gal buckets, thats why i pick that amount.

 

If your tank is partially cycling but still showing positive levels of ammonia and nitrite, how much water would you change how often at this early stage?

Probably wouldn't be doing any water changes unless ammonia was hitting above 2-3PPM and nitrite was above 5. But I would be dosing Prime heavily each and every day if I had livestock in the tank. Though, ideally, you'd move your livestock to a bucket or other container until you get your tank cycled so you don't torture them to death with burned gills.

I guess we agree to disagree lol. Carbon removes pretty much anything that the water absorbs from the air.

There's not really anything to disagree on. Reality is reality. Science is science. No, carbon doesn't remove everything. And you can't account for hormonal, pheromonal and other excretions if you aren't conducting water changes.

I have never had an issue with not doing water changes

You haven't. You aren't everyone and it's important to keep that in mind when giving advice to newcomers who don't fully have a grasp on the basics just yet.

Do you have any info or links that point to fish hormones being released into water causing issues? No trying to prove you wrong...you could be totally correct.

You're welcome to use the search function here on the forum and elsewhere. The easiest way to learn about those excretions would be to start with invertebrates so you can learn how they impact their biological processes. Similar things occur with fish.

i dont care if the guppy fry die or not

Animal cruelty is never acceptable. That's exceptionally terrible advice in 2024. Knowing better and having the means to do better but actively choosing not to is... not great. To say the least.

 

Just an update on today’s water parameters:.

4ppm Ammonia
4-5ppm nitrite
15ppm nitrate

Again, because we've been dosing dechlorination fluid for 48 hours now some of those nitrites might be non-toxic.

I also decided to pick up some Tetra test strips to see how they compare to my API Master liquid kit (answer, not bad). These provided our first measurements of:
pH: 7.3
General Hardness (GH) - 200
Carbonate Hardness (KH) - 20

We also got a TDS meter, which is showing 422ppm
(baseline for our filtered, but non-RO tap water is 358)

Based on somewhatshocked's feedback, will hold for now on a water change but continue dosing dechlorinate. Because we don't have a water stone, I've been dosing 5ml or 1.66x every 24 hours.

I'm struggling to interpret these new readings. Any and all analysis appreciated!

 

I also decided to pick up some Tetra test strips to see how they compare to my API Master liquid kit

Test strips are extremely inaccurate in instances like this.

Based on somewhatshocked's feedback, will hold for now on a water change but continue dosing dechlorinate.

That's not what I suggested. As @Kwyet explained earlier in your thread, Prime =/= mere dechlorinator. Prime is known to help in situations like yours. I can't say the same for the product you're using.

Buy Prime instead of test strips.

 

Test strips are extremely inaccurate in instances like this.



That's not what I suggested. As @Kwyet explained earlier in your thread, Prime =/= mere dechlorinator. Prime is known to help in situations like yours. I can't say the same for the product you're using.

Buy Prime instead of test strips.

Copy that! Prime was ordered and is being delivered this afternoon. Still testing with the API Master kit. Just wanted to get readings for my other water parameters.

Do the pH/GH/KH/TDS numbers worry you for my (dwarf) Honey Gourami or Blue Endlers?

Im happy to report that the fish are all eating and looking pretty relaxed around the tank, at least to my uneducated eye.

 

As I'm waiting for Prime to be delivered and, more slowly, for the tank to finish cycling, I'd like to re-raise the issue of water changes, hormones, and fish welfare.

Before starting this thread, I was unaware of the fish hormone variable. My interest in limiting water changes was driven by practicality, but it was also inspired by the perspective that the YouTube personality Father Fish has on the stress and unnatural disruption that water changes cause to aquarium fish. His view, in short, is that one should only change water if it is polluted. And his approach to planted aquariums (a variant of the Walstad method--lots of plants, proportionally fewer fish) minimizes or eliminates water pollution entirely, at least by conventional metrics.

This raises the question of fish hormones. At the suggestion of others here, I performed a search of fish hormones on this site. Finding only one thread on fish hormones related to a specific breed of fish (Discus), for which there was notable dissent, I widened the search to the interwebs. As best as I can tell based on a preliminary search, the phenomenon as it relates to tropical aquarium fish is under-studied and, as a result, quite controversial. Additionally, as best as I can tell the concern seems to be most prevalent among those who use their aquariums as high density breeding tanks.

Ignoring, for a minute, the lifestyle preference my wife and I have for an (eventually) mature freshwater tank that allows for a month or two between water changes, I am wondering what the implications of fish hormones are for an under-stocked tank with a low-density, high plant-to-fish ratio and a rich soil substrate capped by gravel.

Inspired by the myriad "balanced tank" success stories that abound, not just by @Waters but many others here and elsewhere in the hobby, I'd sure like to better understand what the conditions are in which the fish stresses induced by water changes are offset by the health benefits to the fish.

 

Father Fish

That guy probably isn't worthy of too much of your time beyond being entertainment. He claims water has memory. It's objectively nonsense, to be kind. Specious at best. And his obsession with anoxic filtration is wildly impractical in a way that's been rehashed thousands of times here on this forum alone. Some of the other forums get really nasty about him. We remove personal attacks against him and have removed his attacks on others (some of them kind of scary, to say the least) here through the years. There are still some interesting discussions about it to be found.

His view, in short, is that one should only change water if it is polluted. And his approach to planted aquariums (a variant of the Walstad method--lots of plants, proportionally fewer fish) minimizes or eliminates water pollution entirely, at least by conventional metrics.

First - We probably shouldn't even loosely compare a guy screaming at clouds, so to speak, with an actual scientist and researcher who offers her theories (based in actual science using scientific methods) up in the form of a book for extreme public scrutiny and scientific review. Walstad's hypotheses have changed over time and she's updated and improved upon what she's discovered throughout the years. To the point that she's been on forums, including this one, discussing the importance of water changes. Anything that guy has done is wholly unrelated to her work.

But... neither "method" eliminates or even fully minimizes wastes. They may reduce nitrate but that's not the only thing we're trying to address with water changes.

I am wondering what the implications of fish hormones are

Fish hormones aren't the sole issue here. It's that there are myriad wastes you cannot test or account for with the equipment and resources you have available to you as a hobbyist. You're also trying to replenish mineral content and provide fresh water. That's why it's important to conduct regular water changes. Water is frequently, if not constantly, being changed and refreshed in the wild and that's something we have to account for in our tanks.

Inspired by the myriad "balanced tank" success stories

As you'll discover, there's unfortunately no such thing as a "balanced" tank that requires no effort, no water changes, no nothing. That's why you don't see many of them among the hundreds of thousands of tanks documented here on the forum. They all ultimately fail, look horrendous or are only up for a year or two. It's possible to get to a point where you might only do a water change every 2-3 weeks or so (maybe even monthly) but that won't be the case in the beginning. You'd have to have a ton of relatively fast-growing plants filling the tank and almost no livestock in such a small container of water for that to eventually work well. It will be a hit-or-miss bit of struggle in just 30 gallons. Note that if you went with a shrimp-only tank, you'd likely be able to stretch those water changes out a bit longer.

Important to note that fish aren't inherently stressed by water changes. They're a net positive and are part of their natural life cycle - both in the wild and in captivity. If you're only changing 10-20% of your water every week or so and parameters aren't wildly different, there's next to no impact. Slight parameter variations and temperature shifts are even welcomed by pretty much every species you can keep in your tank, as they spur reproduction, shoaling behavior and molting and hormonal and pheromonal releases for invertebrates like shrimp.

This hobby has been a thing for thousands of years and for at least the past 5-6 decades we've understood the importance of water changes. Things grow and change over time, of course, and every tank is different but we're not exactly reinventing the wheel here. Even with the understanding we've developed in the past 20-25 years about wastes beyond nitrate. Water change necessity is something we can verify with relative ease. If this no/reduced water change thing were something that worked extremely well, you'd find all the millions of hobbyists who've come before you employing those methods on a regular basis.

 

I was just reading back over your thread and realized that while focusing on the water change conversation, there were a couple of other things I had questions about.

First, what is this 24 hour plant deadline you mentioned? Plants can last much longer than that before planting, especially low-tech ones like you have. You can put them in a bucket with dechlorinated water where they can get some ambient light and most plants like that will be fine for at least a week, often longer, so don’t feel like you need to rush.

Second, your stocking is fine, but are you going by the old inch of fish per gallon rule? If so, it’s really out-dated. Instead you want to check on the bioload of the fish you’ll keep (at adult size), how much filtration you have, and the temperament of the species. At the moment you actually have pretty light stocking, even with the very light filtration. A useful tool for future planning is aqadvisor.com. You can enter your tank dimensions, filtration, and desired fish and it’ll give you a calculation of how much of your filtration is being used and recommend a water change schedule, temp, etc. It’s not perfect, doesn’t take plants into account, and is pretty conservative most of the time, but still a useful tool.

 

First, what is this 24 hour plant deadline you mentioned?

This was the timeframe the LFS gave me to get my plants out of their bags and into the water. It hadn't occurred to me to store them in some in-between vessel. Needless to say, despite the immense amount of research I have done, the learning curve in this hobby is quite steep.

At the moment you actually have pretty light stocking, even with the very light filtration.

This is the organizing principle of a Walstad-type aquarium. Using the old rule, if a conventional 30-gallon tank featuring frequent water changes could manage 30 inches of fish, then a Walstad-style aquarium might only support 20, or even just 15 inches of fish. I have played around with aqadvisor.com trying to see how many cardinal tetras I might be able to add. It's pretty cool. But because I am pursuing a tank strategy that is evidently much more unconventional than I realized, though less so than many here seem to think, I find the results difficult to interpret.

there's unfortunately no such thing as a "balanced" tank that requires no effort, no water changes, no nothing. That's why you don't see many of them among the hundreds of thousands of tanks documented here on the forum. They all ultimately fail, look horrendous or are only up for a year or two.

I certainly would not expect a no-effort tank. The hypothesis that led me to this hobby was that there could be a more-balanced tank that required some effort, less-frequent water changes, and some compromise in terms of the flora to fauna ratio.

I am new to this forum, so I can't speak to the universe of tanks here. Given how frequently this forum came up during my research stage as I was googling various aspects of planted tank development, I had thought that the low-tech corner of TPT might be where I belong. But I can certainly attest that there are many hundreds of aquarists over on Aquatic Plant Central, especially on the El Natural sub-thread, who have successful, attractive, long-running tanks with infrequent water changes. While it seems that @Waters has now left this forum, he certainly counted among them.

That said, I am deeply moved by the care and affection that users here have expressed over their fish. I would be glad to learn of tangible, dangerous toxins that threaten the physical or emotional health of freshwater fish--even those in Walstad tanks-- if water is not changed on some kind of weekly basis. If there is evidence of such, I would certainly make alternative arrangements for tank maintenance during our travel season. If there are additional resources you can point me to for learning about what these "myriad wastes" are and how they impact stable tanks that are dirted, capped with gravel, over-planted, under-fished, and filtered by both plants, bottom-feeders, and traditional carbon-based media, I would be glad to know which those wastes are.

 

While it seems that @Waters has now left this forum, he certainly counted among them.

Honestly not entirely sure I'd take anyone seriously when they angrily pick up their toys and run because they were politely corrected by other experienced hobbyists for giving bad advice to a newcomer. They've chimed in twice in eight years with personal insults and reactions like that.

But - I reiterate - there are not tons upon tons of no water change tanks existing for the long-term that both look great and that are healthy. As repeatedly pointed out in this thread and documented pretty much everywhere in the hobby? They are incredibly few and far between. All of the tanks that look nice require effort. All of them. Be that weekly/monthly water changes, fertilizer additions, feeding, detritus removal, trimmings, etc.

You can have a low-maintenance, uncomplicated setup. There are tens of thousands of them documented here. Including most of my own tanks and tank journals that document some of them. Water does have to be changed for tanks to remain healthy. There's no way around it.

Note that more often than not, Walstad-type or dirted tanks take way more effort than simple setups using just pool filter sand or other inert substrate.

That said, I am deeply moved by the care and affection that users here have expressed over their fish. I would be glad to learn of tangible, dangerous toxins that threaten the physical or emotional health of freshwater fish--even those in Walstad tanks-- if water is not changed on some kind of weekly basis. If there is evidence of such

Not sure emotional health is a major thing for most aquatic species, since most of these animals don't have anything resembling true emotions. There are natural behaviors we have to account for, obviously, that do seem somewhat emotional(?) or psychological. And some species are wildly intelligent (like Carinotetraodon travancoricus.) But it should be relatively easy to understand why water changes are important and a required part of the hobby - even if not all tanks are the same or require the same level of maintenance.

The evidence you seek is literally on this forum. In tank journals. In millions of threads. Tens of thousands of newcomers showing up with countless issues that stem from lack of water changes. Tons of them showing up because of "Father Fish", even. Many of those threads go into extreme detail examining parameters, feeding, everything you can think of. The information is there.

If there are additional resources you can point me to for learning about what these "myriad wastes"

I'm not going to do all the work for you (for anyone, not you individually), sorry.

But I will give you some anecdotes that should make sense and point you in the right direction: You secrete and excrete all kinds of things in your daily life, you shed skin cells, sweat, release oils, mucus, gases, keratin, even bacteria and microorganisms. Similar things occur with pretty much all living creatures on earth - including those we keep in our tanks. Those are wastes that need to be removed manually - by you - at regular intervals. They are not all used up by plants, they are not all pulled out via chemical and mechanical filtration, they don't evaporate.

 

Days 10-13: All happy tanks are happy in the same way...

...as Tolstoy might have said. And all unhappy tanks are unhappy in a thousand different ways.

In hindsight, it was predictable that my tank would experience new tank syndrome. By choosing to start the nitrogen cycle by introducing a light load of fish, I unwittingly triggered a spike in ammonias and nitrites that I've been continuing to battle for the last few days. I had hoped that the refrigerated Turbostart beneficial bacteria would perform as it (and the salesman) suggested, but alas. A 30% water change on day 9 (10/14) brought ammonia (and nitrates) down to zero overnight, but nitrites remain unacceptably high. Here's hoping the Seechem Prime dechlorinate I introduced with the water change will detoxify those as I patiently wait for the beneficial bacteria to convert them into helpful (from the plants' point of view) nitrates.

While I wait for the nitrogen cycle to establish, I have another conundrum: My supposedly death-proof plants are looking a bit bedraggled. Some of this is to be expected, I understand, in the transition from emmersed to submerged. But the Hygro Angustifolia Fans are looking decidedly non high-growing. Many of the leaves are looking quite brown and ill.

Thinking that the roots had yet to establish themselves in the potting soil substrate, I had briefly experimented with a squirt of all-in one liquid nitrogen (Thrive+) and a dose of Seechem Excel on day 4 (10/9/24). This probably explains the stepwise increase in nitrates we observe on 10/10/24. I decided to discontinue the fertilization experiment when the nitrite spike emerged the following day and focus on protecting the fish.

Now that we are in a holding pattern waiting for my tank to finish cycling, I think it's time to return to the puzzle of unhappy plants.

Up until now I've been running our Fluval LEDs (one 24-inch Plant 3.0 LED in back, one 24 inch Aquasky 2.0 in front) at 50% maximum intensity on a pretty standard daylight routine. I arrived at this after reading about those whose planted tanks did not have sufficient carbon to support higher-intensity light, with the result being algae. As I'm setting this up as a low-tech tank, I thought 50 percent might be the goldilocks solution.

As I was taking out the recycling yesterday, I noticed the following table on the side of the Fluval Aquasky 2.0 box:

"My god." I thought. The PAR value of these lights falls off exponentially with tank depth. At 18" the light has lost 85% of its plant-absorbable radiation. And my tank is 24" tall! Even with 3.5 " of substrate, that leaves very little light to reach the bottom. Now this is the weaker of my two lights, but still!

As a result, I've decided to increase the light intensity of both lights to 100 percent. And because I can't leave things well enough alone, I've also decided to implement a siesta regimen in hopes that it will increase the amount of available carbon in the tank and help the plants fight off algae.

Wish us luck!!!

 

Your plants may have been grown emersed, or may just be adjusting to your tank and its changing parameters. If you can remove the bad leaves while leaving the best-looking ones, your plants can focus on new growth suited to your tank. Leaving damaged, melting leaves will cause algae. Also, if you change the lighting, try not to change it again for at least two weeks, otherwise it’s another strain on the plants as they have to keep trying to adjust. You may also get some algae with making such a large, abrupt change in intensity. I usually start with 40% and then gradually increase it by 10% increments once the tank stabilizes. I’m not an expert on lighting though, that’s just what works for me.

Walstad’s book was one of the first aquarium books I ever read, and I’ve seen some of her more recent stuff (videos, short articles on some of the changes she’s made). I have great respect for her! I’ve used some of her principles (and other like-minded folk) in my aquariums. I just know from my own limited experience that as I’ve increased the frequency of water changes through the years my tanks have been healthier, more stable and more attractive to view. If I try to pass on what I’ve learned, it’s just to try to help you avoid pitfalls and discouragement, but everyone should do their own research and make their own decisions about what to do with their own tank. I think I (and others here) feel more of an imperative to speak out when we see someone just starting out being given bad advice, and also that’s just the nature of a forum. Hopefully everyone can be adults and thoughtfully discuss the issues!

As for some of the myriad things that can build up in a tank between water changes, just consider what household dust is comprised of (as one example): dead skin cells, dust mites, pollen, dander, non-beneficial bacteria, viruses, molds, ash, cooking and heating residues, other home pollutants. Also, aside from the other things that have already been mentioned, low or no water change aquariums are more likely to experience Old Tank Syndrome, runaway algae, and bacteria blooms (often harmless, sometimes deadly). I’m sure you’re going to do more research, because I can tell you’re that kind of person and want to be a responsible caretaker, so I’m going to leave this topic now and just follow along on this really cool project you’ve started. 🙂

 

Thanks for the kind words, Kwyet, as well as for taking the time to to share your experience. I’m here for the hard truths, even if they put a dent in my initial vision.

That said, I also believe in getting a multitude of perspectives. Reading that Diana Walstad herself frequents Aquatic Plant Central, I raised some of these concerns over there. Two interesting tidbits that emerged were that, first, a heavily planted, lightly populated tank can allow plants to absorb many of the contaminants discussed. And second, that I could also consider deploying a UV internal filter like this.

As I understand it, the fundamental distinction with dirt tanks capped by porous gravels is that the soils beneath can, perhaps with the help of a bottom feeder cleaning crew, also absorb much of the “dust and debris” and recycle it as nutrients.

It may not be a forever tank, but I’m hopeful I can match the performance of others who’ve gotten a year or two or more from their dirted tanks.

Either way, I’m happy to have you along for the ride!

 

Those plants honestly look pretty good to be in a transition like that. Looks like the usual detritus, sediment, biofilm, bacteria, diatoms that are standard early on. I don't see anything, really, that would be attributable to poor lighting. Not sure it's really been long enough for anything like that to be visible just yet.

Since most are slow-growing, lower lighting options, I'd probably run the fixture below 100%. Maybe 75%? Because that's a lot of par when you get closer to the surface with low light plants like Java Fern and Anubias. 100% wouldn't be the end of the world but increases the likelihood of algae and growth issues.

Those crypts(?) are going to sprout new leaves within a month and they'll look stunning compared to the growth that exists right now. You can kinda see it on newer growth but texture, pattern, color, shape are slightly different.

 

That’s correct, @somewhatshocked! Those are Crypt Wendt II Bronze Fans. At least, that’s what it said on my receipt. I’m so very glad to hear that there’s even more to look forward to there.

For the sake of the journal, I should probably list the inventory here. There’s a couple specifics that I don’t have right now: the species of driftwood and the type of rock we used. Next time I go to the LFS I will have to jot those down.

Type Quantity Type Substrate 1 Miracle Gro Organic Potting Soil Scape 1 Driftwood? Scape 3 Rock? Gravel 2 Peace River Super Natural 20lb Flora 2 Anubias Coffeefolia Flora 3 Micro Sword Narrow Fan Flora 2 Java Fern Fan Flora 24 Hygro Angustifolia Fan Flora 2 Crypt Wendt II Bronze Fan Flora 3 Christmas Moss Fauna 2 Dwarf Gourami Honey Yellow Fauna 1 Dwarf Gourami Honey Red Fauna 6 Blue Endlers

 

I’m so very glad to hear that there’s even more to look forward to there.

C. wendtii 'Bronze' is one of the best. I'm biased but give it a few months and you'll see what I mean. Wild that such a cool plant can grow in low light environments.

To illustrate what I mean about how Crypts change, here's a look at less than great Crypts:

That turn into great Crypts:

(All the brown spots you see on leaves aren't holes but snails.)

 

Thanks! Just be aware that internal UV filters like that don’t do much except help with algae spores in the water. They’re too underpowered to kill off many disease pathogens, and even if they are strong enough to do that, the bulbs quickly lose the power to do that. They’ll advertise for yearly bulb replacement, when they’re really only fully functional for about a month. Just what I’ve read, as I have no way to test it.

If you’re getting a cleaning crew, I suggest relying on snails. Anything like a pleco is going to create more waste than you want to deal with in a Walstad tank. Did you get to talk to her directly? That would be cool!

 

Great tip! That one had been on my maybe list for the cleanup crew. Would Black Mollies also be a poor choice for waste? I hear they can do good things for algae cleanup. And they’d look pretty neat, their dark sillouette contrasting the color of our other fish. Shrimp are also on my list. But I don’t think they would clean glass as well as snails?

I suppose it all comes down to how much further we want to push the bio-load. Let’s say we’ve got 10 inches of fish right now. Perhaps instead of adding another signature fish we content ourselves with some handsome, handy utility fish and some snails and call it done.

Fortunately, we have 7 months till summer to find the tank’s initial, year one equilibrium.

 

That is a cool experiment. I never thought of trying that either!

 

I had no idea one could actually isolate ammonia production as you described.

That is a cool experiment. I never thought of trying that either!

It's obviously not scientific and is just anecdotal. Everything depends upon volume, plants, lighting, feeding, health of the critters, other factors we can and cannot control. But everyone should probably try it after quarantining fish just to see what type of ammonia load they're dealing with in their particular setup.

 

Days 13-20: Wild Ride

I was recently reflecting with the El Natural moderator over at AquaticPlantCentral about how many of the mistakes I've made with my first aquarium have been driven by fear. Fear that the plants didn't have enough nutrients in the water column while the roots were establishing themselves into the substrate. Fear that they weren't getting enough light. Fear that algae would take over and that my tank would be reduced to one of those green hazy indoor ponds. All of this fear is nicely reflected in this annotated, updated graph of my journey towards completing the nitrogen cycle in my tank.

Daily doses of Prime throughout this process, along with two internal filters agitating the surface water and keeping oxygen levels up, have kept the fish safe and the experiment fun. But there are several things I would do differently next time:

• No fish-in nitrogen cycling.
• No liquid fertilizer in the early days.
• Do my homework before taking a LFS salesman's word for it when it comes to a fish that I haven't researched.
• Oh, and double my anticipated budget $$$

The new fear is that the cleanup crew which I introduced five days ago to attack the algae may have pushed me over the limit in terms of the bio-load capacity of a Walstad-inspired aquarium. Throughout the early phases of this project I've been repeating the mantra of more plants, fewer fish. But when green dust algae started collecting on the glass, on the driftwood, on the rocks, on every visible surface, I panicked and headed to the local fish store and explained the situation. The salesperson was an older, wiser individual, one familiar with the various editions of Diana Walstad's book. So when he gave the Siamese Algae Eaters a resounding endorsement and assured me that they'd top out around 3 inches, I told him I'd take two. I also wanted a fishy to clean the glass, and you can't simply add 1 or 2 Otocinclus in good concience, so I got 3. A handful of small orange "Sunkist" shrimp for bottom-feeding rounded out the cleanup crew.

Only when I got home did I realize my mistake. While I was admiring the shiny reflective silver skin of the SAEs, I googled them and learned in horror that they can grow up to 6 inches in length. This category of fish was not in the parameters of my 30-gallon Xtra Tall tank. I called the LFS the next day and they assured me that their fish rarely reach 4 inches in captivity, but if I wanted to bring them back no problem. Relieved, I got out my 4 inch net and went to work trying to reverse my mistake. As one Reddit poster put it, SAE are Satan Spawn and nearly impossible to catch. I experienced this myself, uprooting several of my Hygro stems and breaking off many precious Anubius leaves in hot pursuit of these freshwater barracuda--all to no avail. Having painstakingly re-planted the Hygro stems and removed the broken Anubius leaves, I'm thinking that I'm stuck with the SAEs for now.

Which brings me to my new big question: How does one approach calculating fish tank carrying capacity for a Walstad/El Natural, understanding that there is much variation among these?

The inch-per-gallon approach would say that I'm okay. The estimated size of these adult fish (assuming the LFS store is correct about these SAEs only reaching 4 inches) is 27 inches, which is about how much water I have after accounting for the displacement of my substrate and aquascaping.

The aqadvisor.com calculator would say that these SAE once they reach adult length are way oversized for my tank. Oh and I'm also way under filtered.

The general wisdom among planted tank people is filter-shmilter. As the fish grow, so will the plants. As long as I foster a strong, plant-heavy tank to soak up the ammonia I should be fine.

And yet I see many of the Walstad/El Natural folks emphasizing the need for a light bio-load.

If I had it to do over again, I never would've gotten the SAEs. But since I'm stuck with them, for now anyways, I'm wondering if there is any future where they can stay in a tank like this without requiring frequent water changes? They are attractive and interesting fish, and they seem to be playing well with the others.

 

My SAE’s easily got to 6 inches. I think you definitely need to stop listening to the LFS. I wouldn’t keep them in a 30 gallon even with filtration and water changes (and the majority of planted tankers do advocate for filtration in anything larger than about 10 gallons). Also, SAE’s do prefer to be in groups of 5 or so, or at least with similar fish that they can school with. Mine always schooled with the Denison Barbs for instance. For Walstad, you need to think 70% or more of the substrate covered with plants and extremely low bioload. Don’t go by inches.

 

Thank you for confirming my suspicions, Kwyet. I need to get them out and back to the fish store.

Any hot tips on how to do that . As you can see from this thread, SAE are Satan Spawn, they seem to be especially difficult. This gent spent 6 months trying to get one out. That has certainly been my experience.

I approached it by draining 30% of the water from the tank then placing fish food on the surface hoping to draw them out. Unfortunately, they didn't bite. They remained hidden behind rocks and plants. My wife came to help me, trying to draw them out of hiding and into my net. Admittedly I need a second, larger net here. But even then, in an hour of effort only once did I come within a few inches of getting one of them.

Would it be too extreme to do an 80-90 percent drain, rescuing the fish I plan to keep and putting them in the drained water while I go after the SAEs? It will still wreak havoc on my plants, no doubt. But maybe that's the price I have to pay for being foolish here.