[JosephM]

I’m in the process of cycling a 10 gallon, somewhat-heavily planted tank, to be home to a colony of red cherry shrimp that I hope will breed. I only want the best for them and the plants so I want to make sure I’m fertilizing properly. It’s been cycling for about a week and I have osmocote in the substrate, seachem flourish advance to help the roots and stems, and hoping to get some ThriveS for the water column. I’ve heard contrary things about seachem excel maybe being harmful to certain plants or the shrimps themselves. I have some Java moss, anubias nana, dwarf hair grass, and 3 types of stem plants that I don’t know the name of. I want some Marimo moss balls but I’ve heard searched excel might kill them. Just wanted to know if my fertlizing is adequate. And I have high lighting on for 8 hrs a day and inert substrate. R

 

[nicepoeci]

I have never seen any noticeable difference from adding this or any product like it. Some people have even said its an algaecide which I have no idea why they think that because ive used it to treat green water without success. The only way to do co2 is with co2 IMO and I dont use co2 in any of my 30 heavily planted aquariums. Most important thing IMO is a good soil like ADA Aquasoil or Fluval Stratum with a light in which its color spectrum matches the plant well.

 

[Deanna]

Excel works well in supplying carbon for plants in a low-tech setup. It is a common mistake to characterize glutaraldehyde (Excel) as “liquid CO2.” Excel is not CO2. It is a carbon supplement.

RCS are fine with it (I’ve used it with them). However, breeding and longevity have not been studied under various levels of Excel. There are anecdotal comments, in many places, that it is fine for RCS as well as comments that it may not be. You will have to judge, for yourself, which comments you will tend to believe. Perhaps some shrimp experts will chime in here to help.

Glutaraldehyde products, such as Excel or Enhance, will benefit most plants. However, when dosed daily, as per instructions, it may melt Anacharis (Egeria/Elodia), Vals, Duckweed and Marimo moss balls (which are a form of algae). These plants can be trained to use it if adapted slowly by not doing the recommended “initial” weekly dose and then just half-dosing every other day, gradually building up to recommended levels. Vals, for example, will initially melt and then re-grow fully acclimated to it. It will benefit DHG and anubia. I suggest that you start with ½ Seachems' recommended dosage for a few weeks and then move to normal dosing if you have concerns about any for your plants.

As an algaecide, it is very effective against red algae (BBA and various hair-type algae), although best applied with a single high-dose technique (https://www.plantedtank.net/forums/23-algae/1234042-hair-algae-consuming-moss-hc-advice.html#post10762025). It is not effective against GWA, GSA and GDA.

 

[en7jos]

I only want the best for them...

"Best" for the shrimp is not necessarily "best" for the plants, so important to be clear about where your priorities lie. Of course you can have a great planted shrimp tank, but shrimp may not well do as well as they potentially could do in a high tech planted tank with demanding plants, high ferts, CO2 and use of Excel.

Lower tech is generally best for shrimp, typically:
- no CO2
- less demanding plants such as ferns and mosses
- lower ferts / "cleaner" water
- less frequent and smaller water changes (weekly 50% w/c not good for shrimp, think more like 10% bi-weekly)
- no Excel

Others will have no doubt had great success with shrimp breeding rampantly in super high tech planted tanks, so sure this is possible. But most people generally agree that low tech tanks are best for shrimp, if the shrimp are indeed your priority.

Specifically with regards to Excel, most people agree it is "shrimp safe" if you follow the recommended dosing. By "safe" we mean that it is very unlikely to kill shrimp outright. Whether continued daily dosing is harmless to shrimp is unclear; how can you tell if they are not quite thriving as well as they could without it? The conclusion I came to after reading the many threads here on the subject is that:
- Excel is good as algaecide, not really as a source of CO2 in the same way that 'proper' CO2 injection is
- Occasional dosing at the full (high) day 1 rate as per Seachem instructions is fine for shrimp and useful for controlling algae
- Better to avoid dosing regularly as far as possible
- Daily dosing probably not good for shrimp (may not kill them, but probably not best)
- Few would recommend Excel use in a shrimp tank unless you really really need to (better options such as H2O2)

Hope this helps, James

 

[Asteroid]

I’m in the process of cycling a 10 gallon, somewhat-heavily planted tank, to be home to a colony of red cherry shrimp that I hope will breed. I only want the best for them and the plants so I want to make sure I’m fertilizing properly. It’s been cycling for about a week and I have osmocote in the substrate, seachem flourish advance to help the roots and stems, and hoping to get some ThriveS for the water column. I’ve heard contrary things about seachem excel maybe being harmful to certain plants or the shrimps themselves. I have some Java moss, anubias nana, dwarf hair grass, and 3 types of stem plants that I don’t know the name of. I want some Marimo moss balls but I’ve heard searched excel might kill them. Just wanted to know if my fertlizing is adequate. And I have high lighting on for 8 hrs a day and inert substrate. R

Starting off a tank with high light and no co2 is a recipe for disaster. Hairgrass really needs co2 to spread and grow well. If it grows slowly or at all it usually becomes full of algae since debris settles there. I have hi-tech tanks with exploding RCS populations. Both are co2 and heavily dosed. Absolutely no effect on shrmp. Most important is clean water.

Excel is safe for all if used as directed. It's not a replacement for co2, but can aid plants in there uptake of nutrients by keeping plant surfaces clean IMO.

 

[Blue Ridge Reef]

I've not been convinced that Excel provides any more carbon to plants than good surface agitation does; Karen Randall broke it down in her article about glutaraldehyde a few years back. I'm loathe to link it because it's been rehashed here enough times already but it's easy enough to Google. Excel does have plant benefit, if only reducing biofilm and algae growth on leaves which make it more difficult to uptake nutrients (surely including CO2). As someone who puts shrimp in pretty much every aquarium, I use very little of it in my established tanks these days. When I do, it's usually sprayed on hardscape or Anubias leaves (out of water) for BBA. The reason I don't like to use it in shrimp tanks is simple: shrimp eat biofilm and Excel kills it.

Couldn't agree more that high light and low tech is an uphill way to start. I also agree you can keep shrimp in high tech just fine. I have 2 high tech tanks of my own with thriving shrimp populations. While it can be done, the large water changes you tend to do in them are not the best way to keep shrimp but populations seem to adapt. That said, if my goal is to breed shrimp, then their needs outweigh any needs of the plants. Pressurized CO2, Excel, nor heavy fertilizers of any kind would be used if I were tasked with setting up the best shrimp tank I could and water changes would be small and frequent.

 

[Tiger15]

Glut is an effective Algaecide but to say that it is liquid carbon is just marketing gimmick. Seachem recommends 2 ppm Glut initial high dosage and 0.4 ppm daily thereafter, so even if one assumes 100% conversion to CO2, its minuscule compared to good air exchange that can achieve 2 to 3 ppm CO2 at equilibrium with the atmosphere.

Toxicity tests have shown that Glut is toxic to glass shrimp at 41 ppm. So the recommended dosage is safe to adult shrimp as I’ve done it occasionally to my shrimp tank many times. But there were no tests on shrimp hatching and larvae, so the impact of regular dosing on reproduction is unknown as many trivial factors can stop shrimp from multiplying.

 

[Deanna]

While I agree that high light in a low-tech tank is a recipe for algae and sub-performance of plants, we don’t actually know that the OP has truly “high lighting”, since we don’t know the PAR or make of the light. If the light is too much, Excel will not help in this regard. However, Excel is very helpful when light is being pushed a little too much in a low-tech tank, but not so much as to overwhelm the benefit. It is at these moderately high light levels, for low-tech tanks, where I have found maximum benefit of Excel.

Plants use up the atmospherically-sourced CO2 much faster than it equilibrates in water (ignoring carbon from fish, bicarbonates and organic matter). The most CO2 you are going to get from optimum, not maximum, surface agitation is about 2-4ppm (assuming alkaline conditions) and remember: Excel is not CO2, so it won’t de-gas from surface agitation. Walstad recommends limiting surface agitation to provide just a sufficient O2 level for the inhabitants in order to not drive CO2 off.

With the little bit of CO2 in low-tech tanks, it may be best to dose Excel midway through the photoperiod, as photosynthesis may consume the little bit of CO2 available sometime during the photoperiod. It may be possible to easily measure the CO2 variations in a low-tech tank by using pH to determine when a particular tank needs Excel supplementation. For example, the difference between a CO2 level of 1ppm and 3ppm will be about .5 pH.

I have seen that Sunken Gardens article many times and much of the info is based upon theory and the rest describes the mechanisms by which glut is known to kill cells (a different application altogether). It is not known exactly how glut works in plants (no one has performed any radioactive tracing), although explanations generally relate to the Calvin cycle. T. Barr has commented that Excel does seem to add more carbon than can be predicted by what is known about glut. The Sunken Gardens article is primarily designed to warn users away from Excel because of the supposed dangers inherent in glut. However, if we took that attitude to other products, we wouldn’t use bleach, alcohol (which some of us drink), H2O2 …and the list goes on an on. In fact, virtually every man-made thing is known to the state of CA to either cause cancer or birth defects. The article actually suggests that glut can cause diseases such as lupus!!

 

[Blue Ridge Reef]

I have seen that Sunken Gardens article many times and much of the info is based upon theory and the rest describes the mechanisms by which glut is known to kill cells (a different application altogether). It is not known exactly how glut works in plants (no one has performed any radioactive tracing), although explanations generally relate to the Calvin cycle. T. Barr has commented that Excel does seem to add more carbon than can be predicted by what is known about glut. The Sunken Gardens article is primarily designed to warn users away from Excel because of the supposed dangers inherent in glut. However, if we took that attitude to other products, we wouldn’t use bleach, alcohol (which some of us drink), H2O2 …and the list goes on an on. In fact, virtually every man-made thing is known to the state of CA to either cause cancer or birth defects. The article actually suggests that glut can cause diseases such as lupus!!

I didn't link the article just to avoid the conversation going this direction, but since we're here, what I did (do) find most valuable about it is the dissolution rate of carbon in the updated version. I'd pay real American dollars to have Tom Barr's data, but as far as I'm aware he signed an agreement of incommunicado. Since we're talking about the article though, it would only right to anyone reading to share the link: https://www.sunkengardens.net/blog/...d-co2-and-the-dangers-of-glutaraldehyde-az2w7

Lupus was mentioned in a throwaway sentence regarding the potential autoimmune response to repeated exposure. And though I see where she was going, I'll agree that sentence would have best been omitted. She could have gotten her point across without it, and I feel it taints the whole piece as hyperbolic.

I no longer use it in my own tanks with shrimp. But in this thread, OP said he has set this tank up and wants the best for his shrimp and plants and wants to fertilize properly. I would suggest he cater to the less hardy life form in this case and would personally even go light on NPK fertilizing, and even moreso on micros -let alone adding glut.

 

[Tiger15]

Glut is harmful to human only if one is exposed to the chemical in high quantity regularly, such as lab and biocide application workers. Thus, health and safety regulations require such workers to wear protective gear to cut off inhalation and dermal contact exposure pathways. Hobbyists who only infrequently dose small quantity is not going to be at risk. This is similar to exposure to sunlight. Extended exposure to sun UV light can cause skin cancer but infrequent exposure to sunlight is helpful in making Vitamin D.

Agitation will drive off CO2 only if the tank water contains more CO2 than the atmosphere. In a low tech tank during photo period, CO2 is depleted by plants and agitation will drive in, rather than drive off, CO2 from the atmosphere. I have a zero tech planted shrimp bowl by the window and at the peak of the sunlight period, I recorded CO2 stripped to 0.1 ppm and pH rose to 8.8. If I could provide agitation to replenish CO2 which I don't, growth would be explosive out of control.

I used up 1 gal of Glut (Metricide 14) a year in my high tech tanks which I administered high initial dosage weekly after water change for many years. It is very helpful to prevent algae, keep leaves and hardscape clean, and I've never observed harm to my fish, fry or egg hatching, but I have no shrimp in it to know if it will affect their reproduction. Occasionally, I dosed Glut to my zero tech shrimp bowl. I do it as an algaecide, not liquid carbon, as even if 100% Glut is convertible to carbon, it is only 2 ppm at the initial high dosage, too little and no better than I could provide by agitation.

 

[Deanna]

Agitation will drive off CO2 only if the tank water contains more CO2 than the atmosphere. In a low tech tank during photo period, CO2 is depleted by plants and agitation will drive in, rather than drive off, CO2 from the atmosphere.

I agree with everything, but the above part. There is quite a bit of CO2 created by the combination of fish, bicarbonates and, perhaps mainly, decomposition. It is this CO2 that we don’t want to drive off through agitation. Capitalizing on these sources is one of the goals in a low-tech rank. In a high-tech tank, maximum agitation is the goal.

 

[Tiger15]

I agree with everything, but the above part. There is quite a bit of CO2 created by the combination of fish, bicarbonates and, perhaps mainly, decomposition. It is this CO2 that we don’t want to drive off through agitation. Capitalizing on these sources is one of the goals in a low-tech rank. In a high-tech tank, maximum agitation is the goal.

What you said is true at the beginning of the photo period. But as the photosynthesis progresses, CO2 will decline at a rate depending on the plant mass, bio load, and light intensity. At some point, there is likelihood that CO2 drops below atmospheric equilibrium level and agitation is helpful to replenish lost CO2. This has been observed in natural lakes and NPT as reported in Walstad book. In my NPT shrimp bowl, CO2 drops to 0.1 ppm half way into the sunlight period. You can map out your CO2 time profile by measuring pH during the photo period using kH-pH table calculation such as this. https://www.rotalabutterfly.com/co2-ph-calculator.php

Agitation to replenish CO2 is best achieved by surface breaking by means of HOB or canister filter. Air stone has a net effect of stripping off CO2 more than replenishing it as CO2 has an affinity to attach to rising bubbles. This is why you can use air stone over night to determine off gas pH level of your tap water.

 

[ChuckM]

...Glutaraldehyde products, such as Excel or Enhance, will benefit most plants. However, when dosed daily, as per instructions, it may melt Anacharis (Egeria/Elodia), Vals, Duckweed and Marimo moss balls (which are a form of algae). These plants can be trained to use it if adapted slowly by not doing the recommended “initial” weekly dose and then just half-dosing every other day, gradually building up to recommended levels. Vals, for example, will initially melt and then re-grow fully acclimated to it. It will benefit DHG and anubia. I suggest that you start with ½ Seachems' recommended dosage for a few weeks and then move to normal dosing if you have concerns about any for your plants.


As an algaecide, it is very effective against red algae (BBA and various hair-type algae), although best applied with a single high-dose technique (https://www.plantedtank.net/forums/...ae-consuming-moss-hc-advice.html#post10762025). It is not effective against GWA, GSA and GDA.

I'm just gonna add a "me too" to this. I haven't done deep analysis of Excel, but I did have a BBA problem in a 6 gallon and decided to use according to directions. While I think it knocked bask the BBA, I believe it pretty much wiped out the Duckweed I had. I accidentally introduced the Duckweed a year ago but have come to appreciate it. Coincidentally when I started the Excel the Duckweed started to disappear till I now have a few leaves floating around but it's mostly gone. I stopped the Excel 4 weeks ago and see the Duckweed starting to come back, as well as the BBA. Also, 2 Amanos and 2 Nerites didn't appear to suffer for it.
YMMV!

 

[Tiger15]

I'm just gonna add a "me too" to this. I haven't done deep analysis of Excel, but I did have a BBA problem in a 6 gallon and decided to use according to directions. While I think it knocked bask the BBA, I believe it pretty much wiped out the Duckweed I had. I accidentally introduced the Duckweed a year ago but have come to appreciate it. Coincidentally when I started the Excel the Duckweed started to disappear till I now have a few leaves floating around but it's mostly gone. I stopped the Excel 4 weeks ago and see the Duckweed starting to come back, as well as the BBA. Also, 2 Amanos and 2 Nerites didn't appear to suffer for it.
YMMV!

It’s good to learn that excel can inhibit duckweed. There are numerous inquiries including myself on how to eliminate recalcitrant duckweed, and excel appears to be a simple solution. Exclusive (not amphibious) aquatic plants such as Vals, mosses and Hornwort are sensitive to excel, and I guess duckweed is one of them. I once had hitchhiked mosses I had difficulty getting rid of until I dosed excel at high dosage daily for one week.

 

[Blue Ridge Reef]

I've never noticed it killing duckweed nor Java moss. Currently have a couple of tanks I can't seem to get either completely rid of. I'd say a prayer for the shrimp and do the initial high dose on them right now if I thought it would help get me back to a clean slate but unfortunately both have Vals and one has tons of fissidens moss. Curious to see if more people have seen DW or JM decline with Excel usage.

The best tip I ever got for removing duckweed was set aside 10 days, then every day remove most of it, at least over half. That way you're not laboring over the tank for hours and it isn't too big a chore. By the end of a week, you're looking for any bits to remove. The problem in these 2 tanks is some always seems to get pushed under the surface from the filter outputs and resurfaces a week or so later. By the time I notice it, there are patches of it spreading around again. We joke about it being a great thing but one of the downsides of multiple tank syndrome is your attention is too divided.

 

[ahem]

Excel works well in supplying carbon for plants in a low-tech setup. It is a common mistake to characterize glutaraldehyde (Excel) as “liquid CO2.” Excel is not CO2. It is a carbon supplement.

RCS are fine with it (I’ve used it with them). However, breeding and longevity have not been studied under various levels of Excel. There are anecdotal comments, in many places, that it is fine for RCS as well as comments that it may not be. You will have to judge, for yourself, which comments you will tend to believe. Perhaps some shrimp experts will chime in here to help.

Glutaraldehyde products, such as Excel or Enhance, will benefit most plants. However, when dosed daily, as per instructions, it may melt Anacharis (Egeria/Elodia), Vals, Duckweed and Marimo moss balls (which are a form of algae). These plants can be trained to use it if adapted slowly by not doing the recommended “initial” weekly dose and then just half-dosing every other day, gradually building up to recommended levels. Vals, for example, will initially melt and then re-grow fully acclimated to it. It will benefit DHG and anubia. I suggest that you start with ½ Seachems' recommended dosage for a few weeks and then move to normal dosing if you have concerns about any for your plants.

As an algaecide, it is very effective against red algae (BBA and various hair-type algae), although best applied with a single high-dose technique (https://www.plantedtank.net/forums/23-algae/1234042-hair-algae-consuming-moss-hc-advice.html#post10762025). It is not effective against GWA, GSA and GDA.

I can confirm that as proper dosing levels (per the bottle instructions), it did not harm my duckweed and Marimo balls have grown and look very healthy, I’m sure not from the excel but it did not harm them.

I never do the “initial dose”, just go to the daily and stick to that.

I only have anecdotal evidence and speculation on its action against algae. It appears to have most effect in hair type algae, whether red or green types. When I’ve started using it after an outbreak it would correlate with algae disappearance, although I was typically doing many anti-algae things at the same time. I’ve never noticed any effect with GSA nor GDA. Not sure about green water. My guess is that some algae may actually use it like plants do, where for others it’s toxic.

 

[Tiger15]

I've never noticed it killing duckweed nor Java moss. Currently have a couple of tanks I can't seem to get either completely rid of. I'd say a prayer for the shrimp and do the initial high dose on them right now if I thought it would help get me back to a clean slate but unfortunately both have Vals and one has tons of fissidens moss. Curious to see if more people have seen DW or JM decline with Excel usage.

Good luck to your shrimp and keep us update how they do.

I can’t speak for duckweed, but for Java moss following the instruction of high initial dosage and low dosage daily thereafter will not kill it. But dosing high initial rate every day for a week will kill mosses based on my experience.

 

[Deanna]

It appears to have most effect in hair type algae, whether red or green types.

Green hair types are of the "red" family. The "red" indicates that the algae turns red when hit with alcohol.