[Storm]

I have a heavily planted low tech shrimp tank. Right now there are only 15 CRS and 2 Amano shrimp in there. For plants I have Anubias Nana, Java Fern, Java Moss, Fissidens Fontanus, Marsilea Minuta, Crypt Parva, and Crypt Lutea.

The tank is basically planted wall to wall. I test my water weekly with an API test kit and have been testing 0 ammonia, 0 nitrites, and 0 nitrates.

My question: Is there any reason to do a water change if all my tests are 0?

I understand that most of the time the weekly water change is recommended to reduce the total amount of nitrates, after the bacteria has had a chance to process ammonia into nitrite and nitrite into nitrate, but it seems like my tank is so heavily planted that my plants suck up any nitrate.

The shrimp seem very healthy and happy, but I'm concerned about the long-term risks of not changing water. Is there any other reason I should be changing water?

The tank has been established and running for about 5 weeks so far.

 

[zachary908]

I suppose it's possible your shrimp could use up the important minerals in your water... water changes normally replenish them.

 

[audioaficionado]

Plants don't take up all chemicals that will build up with time.

 

[Storm]

Plants don't take up all chemicals that will build up with time.

Thanks, that's what I'm looking for. So, would you recommend weekly 25% water changes, or given the 0/0/0 tests can I get away with less frequent?

 

[audioaficionado]

25% sounds reasonable.

 

[Coursair]

Cherries are fine w PWCs. CRS are much pickier and you may want to do smaller WCs. Like 10% and use R/O or Distilled water. Either reconstitute w Shrimp mineral additive or perhaps 2-3 parts Distilled to 1 part conditioned Tap water ??

I'm still a noob at Shrimp. I've always advocated 25% PWC for my fish. Some higher grade CRS Shrimp are much more sensitive.

I'm trying to read up on them and learn as fast as I can. Ask Nikki or the person you got your Shrimp from (if it's a breeder).

 

[d3javu]

Depending on the parameters of the water before being treated (your tap water i'm assuming), hardness and other minerals, you likely could greatly reduce the amount of water in the changes, and possibly even reduce the frequency of the water changes, but I would still conduct water changes nonetheless. Even though nitrates/ammonia/nitrites might be nonexistent, minerals and other elements are still in the water. For example when water evaporates it leaves behind the calcium and other minerals behind.

This could be a problem in specific situations, for example, if you have extremely hard water and are keeping a soft water plant/fish that is sensitive to the water, the build up of deposits from water evaporating and/or new minerals being deposited when "topping off" could be more than the flora/fauna can handle.

In most cases reducing the amount of the water change would be ideal to reducing the frequency or dropping WC's all together

 

[Storm]

Depending on the parameters of the water before being treated (your tap water i'm assuming), hardness and other minerals, you likely could greatly reduce the amount of water in the changes, and possibly even reduce the frequency of the water changes, but I would still conduct water changes nonetheless. Even though nitrates/ammonia/nitrites might be nonexistent, minerals and other elements are still in the water. For example when water evaporates it leaves behind the calcium and other minerals behind.

I have an API freshwater test kit, but that only tests PH, ammonia, nitrite, and nitrate. I'm using carbon filtered tap water (from a fridge filter) which has a PH 7.0 and 0/0/0 for everything.

What test kit should I get to test the Kh/Gh so I know whether I need to add minerals or not? I think my tap water is actually pretty hard, and I feed my shrimp Ken's pellets with calcium so they are getting plenty of calcium - they molt every few days which is encouraging.

I appreciate your input. Perhaps a smaller water change is in order. I think the carbon filtered water removes all chlorine/chloramine but I treat the water anyway just to be sure.

 

[d3javu]

The easiest way to find out what minerals are in your tap water is to call the city and they should be able to at the very least direct you to the water treatment facility, or if you already know who they are then just give them a call up, I believe by law you are able to obtain some sort of print out or information regarding the composition of the water.

If you are in an area with an abundance of minerals in the water, you may consider replacing a majority of the water in the tank with R/O (Reverse Osmosis) water. In that case you could just top it off with more R/O water and just add macros/micros as you see fit.

 

[audioaficionado]

Try looking up your local water supply quality report online. I just did my city tap water supply and it's fairly soft and pure and is usable after dechlorination. Not RO but close enough for me. I'll definitely be adding some GH booster during water changes.

I have an API freshwater test kit, but that only tests PH, ammonia, nitrite, and nitrate. I'm using carbon filtered tap water (from a fridge filter) which has a PH 7.0 and 0/0/0 for everything.

What test kit should I get to test the Kh/Gh so I know whether I need to add minerals or not? I think my tap water is actually pretty hard, and I feed my shrimp Ken's pellets with calcium so they are getting plenty of calcium - they molt every few days which is encouraging.

I appreciate your input. Perhaps a smaller water change is in order. I think the carbon filtered water removes all chlorine/chloramine but I treat the water anyway just to be sure.

South Central Connecticut Regional Water Authority 2010 Water Quality Report

 

[Storm]

Try looking up your local water supply quality report online. I just did my city tap water supply and it's fairly soft and pure and is usable after dechlorination. Not RO but close enough for me. I'll definitely be adding some GH booster during water changes.


South Central Connecticut Regional Water Authority 2010 Water Quality Report

Thanks for the link - how do I read it to determine mineral content (hardness)? It looks like it is fairly pure - only 1 ppm nitrates (doesn't even show up on an API test kit to me) and my carbon fridge filter will probably remove any of the heavy metals or other things.

I believe my tap water is good, but it's hard to tell what the kh/gh numbers are from the CT report.

You've been very helpful.

 

[kirk]

i would keep to what these folks said above and i regularly do 25% Wc a month in my lowtech...

having said that i recently had a job that kept me so busy for three months that i did'nt get around to doing any tank maintenance. It was at least three months before i did a water change more like 3 1/2 and my water params did test ok. The sponge filter (only filter on 46 gal. bowfront) was so clogged that circulation was practically nill.

Crystal reds(6) were fine along w/ the rummynose(3) and otto's(3). Water looked very clear. And like i said water tested fine. But there was a bunch of hair algae and dust algae... prob keeping things in balance or trying. It was a small bioload for this tank. The tank is looking much better now...Phew!

I'm not suggesting that it's a good idea and it was no fun looking at that tank, but it's amazing what a natural ecosystem, even in a tank, can do.

 

[audioaficionado]

I believe my tap water is good, but it's hard to tell what the kh/gh numbers are from the CT report.

It sure is because it isn't listed. Dorks! What good is an incomplete water report

Just test the KH/GH yourself or call 'em up and ask.

 

[astrosag]

Echo the other posters. Water changes, properly done, are a good insurance regardless of what you're test kits shows. Old water is old water too.

I would change water based on what's appropriate for the most sensitive shrimp you have in the tank. Since your tests kits are showing favorable results, you can get away with small changes. Usually, in small tanks, large water changes are preferred but with finicky shrimp you gotta be careful.

Anything nearing 25% should be good imo. Your shrimp would probably survive w/o water changes but I also think water changes would also make them happier and promote healthier shrimp.

Remember, in the wild nearly all fauna/animals we use are used to flowing water. It's unnatural for them to be stuck in the same water - that thought alone makes me want to do water changes lol.

 

[Mxx]

I don't know, to answer the OP's question. I'd been asking the same thing about WC's and it came up inconclusive for me. It seems possible that the organic chemistry happening in our tanks is more complicated than we'll be able to fully comprehend, and that water changes are an insurance against this. Or not.

Many people do run tanks with no WC's for years, sometimes no filtration even, relying purely upon plants for that. If you top off with filtered tap water that may remineralize the water as necessary in perpetuity, but check whether your hardness builds up in time. Or as said, you can top off with RO water, and add the necessary minerals yourself.

It seems a soil underlay and relatively low lighting is best for low-maintenance tanks in the long term, as you don't really want to be doing much or any dosing without WC's. And read Diana Walstad's book, which discusses these matters in detail.

The use of carbon, and possibly the use of purigen, may also take out those other compounds that water changes otherwise might.

Unfortunately it seems that many of our practices are based more upon conjecture than rigorously proven facts, so you'll need to arrive at your own conclusions. But many people also do run successful no WC's tanks, so even though we may not know exactly why, it's clear that it can and does work not to do them.

Of course, not that WC's will hurt in most cases, though they do take your time and to some degree can destabilize your system regularly resulting in things such as algal blooms. But if you're not doing WC's then I'd suggest you at least test regularily to ensure that things are okay and for instance that your PH and hardness don't crash. It might help to add a handful of crushed coral or dolomite to your filter and let them dissolve slowly in time to buffer against that. Good luck either way.

I'm about to set up a low maintenance shrimp tank myself.

 

[Storm]

Well, I did about a 33% water change yesterday just to "catch up."

What was amazing was how clear the water was after I did the change. The water I removed had a slight greenish/yellow tint to it. Now I can actually see my plants and driftwood better.

I think water changes must still be important regardless of ammonia levels. There are just too many other organic compounds that end up in our water to risk it.

Thanks for everyone's input. The idea of running a Diana Walstad no maintenance tank is appealing, but you really have to get the balance right before you can eliminate all water changes.