Iodine in your tank

[GaspingGurami]

Hello, I'm not sure where to post this under, so mods, pls move this to the Freshwater fauna section if you deem this to be more suitable in that forum, thanks.

Read somewhere that shrimps do better with a monthly dose of iodine. If I recall rightly, the iodine used is the same as those used for marine tanks, but dosing in half the amounts recommended for marine water setups.

This iodine, I read, stabilizes the shrimps, stimulates reproduction, improves hatching rates and is no harm to the fish and plants if used in those trace levels.

Anyone with experience care to comment or confirm the truth/fallacy of this? I'm just trying to make my shrimps (that don't have pincers) live for longer than a month.

[theodore]

Trace solutions we add for our plants already contains traces of iodine. While I'm not sure if iodine benefits freshwater shrimps, I think you should look elsewhere if your shrimps are dying within a month.

What kind of shrimps are you keeping and how are the tank conditions like?

[GaspingGurami]

[quote:4943477c71="theodore"]Trace solutions we add for our plants already contains traces of iodine. While I'm not sure if iodine benefits freshwater shrimps, I think you should look elsewhere if your shrimps are dying within a month.

What kind of shrimps are you keeping and how are the tank conditions like?[/quote:4943477c71]

Well, I dunno if I have an old tank or not -- fauna and decor was over a year old, plants more than 6 months, but recently, I have lost all my yamatos and many neon tetras due to poor dosing calculation. I have not redone the tank except for massive daily water changes and blackout.

After blackout, I trimmed as much as I could, changed water and added liquid ferts. When my tests showed water is more or less stable, I added Yamatos which promptly died. This way, I've killed more than 20 shrimps bought in separate batches of 2 - 4 each time so far.

Over an average, my present water has:
Ammonia: 0
Nitrite: 0-0.1ppm
Nitrate: 20ppm
Phosphate: 1-2ppm
pH: 6.7
kH: 5 degrees
gH: 3 degrees
Temp: 28-30 degrees

Looks like I have no luck in keeping Yamatos. On hindsight, I even wonder if those shrimps I previously had were yamatos as they were carrying eggs in their swimmerettes, and were changing colours. I understand Yamatos don't breed in freshwater. I have only successfully kept these kind of shrimps, and feeder shrimps with any success. OTOH, all the yamatos I have got so far will perish on me within the night

I'm not trying to breed shrimps, I only hope to be able to have a couple of algae eating shrimps clear off the remnant hait and brush algae that the Oto won't touch. Thus my wish to be able to keep these things alive for longer than a month.

[theodore]

Changing colours? Check the AQ gallery for pictures of yamato and malayan shrimps and see if you have gotten the latter.

Your water parameters look ok though you may want to do something to lower the temperature. 30 deg C is too near their upper limit and acclimitizing new shrimps at this temperature may a little more difficult usual.

[PeterGwee]

Lawrence, you don't need critters to get rid of algae. Its a plant growth and maintenance issue in your case if algae is a problem. Working towards improving plant growth and trimming off the algae is the way to approach things in your case.

The constant death of new shrimps being added to your tank tells us that something is pretty wrong with either the addition of CO2(unstable..OD), O2(too low in the night?) or water conditions (You have been doing massive water changes to correct conditions based off lousy kits? Generally, I don't bother with them anymore. Once or twice of 50%-70% water change should clean things up pretty good and you can redose the nutrients back 2-3x per week and keep up on the large weekly water changes.). You need to check on all this carefully...(CO2..measure the pH and KH both in the am and pm times...is it stable?). O2 (Are your critters gasping in the morning? Add an airstone at night and see if the new shrimps perish again.). All this issues points to one main thing...the plants are not growing well. Focus on plants and stuff that makes them grow well and stop worrying about the algae except trimming and removing them during weekly maintenance. Oh..one more thing...plant heavily if your plant mass is low.

Regards
Peter Gwee

[GaspingGurami]

[quote:6b8aad43fe="PeterGwee"]Lawrence, you don't need critters to get rid of algae. Its a plant growth and maintenance issue in your case if algae is a problem. Working towards improving plant growth and trimming off the algae is the way to approach things in your case.

The constant death of new shrimps being added to your tank tells us that something is pretty wrong with either the addition of CO2(unstable..OD), O2(too low in the night?) or water conditions (You have been doing massive water changes to correct conditions based off lousy kits? Generally, I don't bother with them anymore. Once or twice of 50%-70% water change should clean things up pretty good and you can redose the nutrients back 2-3x per week and keep up on the large weekly water changes.). You need to check on all this carefully...(CO2..measure the pH and KH both in the am and pm times...is it stable?). O2 (Are your critters gasping in the morning? Add an airstone at night and see if the new shrimps perish again.). All this issues points to one main thing...the plants are not growing well. Focus on plants and stuff that makes them grow well and stop worrying about the algae except trimming and removing them during weekly maintenance. Oh..one more thing...plant heavily if your plant mass is low.

Regards
Peter Gwee [/quote:6b8aad43fe]

Hi Peter,

You kinda like hit the nail on its head. The word is maintenance. Trimming off the big leaves with bba is one thing, but I draw the line when it comes to trimming tennelus leaves, let alone gravel that has bba.

Incidentally, these were remnants from my last outbreak, and although there is an uneasy truce in the battle, some of the remnant algae are a thorn in the flesh. So I thought, some shrimps will be nice -- I've enjoyed watching their industrious pincers at work, and as a bonus, I get the last bits of algae removed

My pH reading is quite constant before and after photo period, I get around a pH 6.9 before the lights and CO2 comes on and 6.7 when they go off. I have cut my CO2 down so that I don't OD on it anymore I've been going without the test kits except kH/gH and pH, but recently I've tested for ammonia and nitrite for the shrimps. I Change 50% water a week, top up 1.5 litres daily for evaporation and dose 1.5ml of LGA daily.

Plant growth has not slowed, I am still busy trimming the stem plants that in frustration, I recently cut them all down to the roots and replanted with corkscrew vals. Even then, 1 cabomba has managed to send a shoot up to the surface within a week. E. oriental puts out a new leaf every week and now has a stalk of strange hairy balls above the water. tennelus are beginning to grow on top of each other and the riccia had just floated off from its bogwood as it is too big to stay tied down. In short, I dare say my plants are growing a bit too fast, but O2 is visibly lacking

I mean despite all these growth in such a small tank, I believe the O2 level should have reached saturation levels easily -- there is so much plants that every piece of gravel is planted except the small plot under the bogwood. However, I note that the plants hardly bubble now-a-days, and the riccia makes a pathetic show of producing a pinprick of a bubble at their tips. This is something I don't understand.

Thru this all, the fishes are not gasping anymore in the morning (probably have acclimatised to my CO2 OD), but not taking chances, I ran the airstone from lights out till an hour before lights on for the sake of the shrimps beginning from this batch. Even then, 1 have succumbed after 2 days and a night.

One common phenomena that I noticed with all shrimp fatalities are that the shrimp will feed on some algae, and after a few hours, start swimming around the tank non-stop, then they faint and drop dead. I was wondering if bba can store up heavy metals in their cells such that when shrimps feed on them, they die of poisoning? Just guessing.

[eriond]

Anyone with experience care to comment or confirm the truth/fallacy of this? I'm just trying to make my shrimps (that don't have pincers) live for longer than a month.[/quote]

HI there,

Just to share my experience with you on shrimps. Yamato (and most fresh water shrimps) are particularly sensitive to water parameter and will 'faint off' after being introduce into a tank for about a few hours. Normally when I buy them, I will put the whole bag unopen in the tank for about 1/2 hour to allow temperature to stabilise to that of tank. Then I open the bag, introduce some water from tank to bag, do it again 15mins later, again 15 mins, then I introduce them into the tank. This way I only lost 1 yamato out of 25. After some time of acclimatization, Yamatos become probably the hardiest survivor ! All mine are still alive today. I know this is troublesome, but no pain no gain. Remember temperature must NOT exceed 28degrees for too long or else they will die. 28 is the absolute max they can tolerate. Hope this help

[hobbit6003]

It's interesting to see people attributing the deaths of shrimps to CO2 OD.

Believe me, it'll take quite a fair bit of CO2 to actually kill your shrimps. Fishes like swordtails and mollies were reportedly able to withstand CO2 concentration up to 800ppm.

For me, I've had about pH of 6.1 and kH of 4 at one stage, which would give me a CO2 reading of 95ppm. Nothing happened to my yamatoes and my apisto bred, which was my objective.

At the present moment, I'm maintaining my CO2 concentration consistently at 60-65 ppm throughout.

Cheers,

Kenny

[GaspingGurami]

[quote:f7f922ee6f="theodore"]Changing colours? Check the AQ gallery for pictures of yamato and malayan shrimps and see if you have gotten the latter.

Your water parameters look ok though you may want to do something to lower the temperature. 30 deg C is too near their upper limit and acclimitizing new shrimps at this temperature may a little more difficult usual.[/quote:f7f922ee6f]

I probably got Malayan shrimps instead of yamato. Can't tell for sure as they are almost the same shape and so small. However, I recall they don't have a white line running down the middle and faint red marks that I see on the yamatos I now have.

However, I recall them carrying eggs after their introduction to my tank. Depending on what they eat, their colour changes accordingly. Black for BBA , Yellow for rotting banana leaf , rust for fish pellets .

Those Malayan shrimps are more hardy than yamatos IMO. However, my present yamatos have made it past the 2nd day mark! I think the key to my problem is O2. Running the airstone through the night seemed keep them happy. I'll keep observing for a while more before concluding that it is O2 that is deficient, and then figure a way out of this.

Eriond wrote:

Just to share my experience with you on shrimps. Yamato (and most fresh water shrimps) are particularly sensitive to water parameter and will 'faint off' after being introduce into a tank for about a few hours. Normally when I buy them, I will put the whole bag unopen in the tank for about 1/2 hour to allow temperature to stabilise to that of tank. Then I open the bag, introduce some water from tank to bag, do it again 15mins later, again 15 mins, then I introduce them into the tank. This way I only lost 1 yamato out of 25. After some time of acclimatization, Yamatos become probably the hardiest survivor ! All mine are still alive today. I know this is troublesome, but no pain no gain. Remember temperature must NOT exceed 28degrees for too long or else they will die. 28 is the absolute max they can tolerate. Hope this help

Thanks, I have been practicing that for all fauna that I introduce to my tank.

Kenny wrote:

It's interesting to see people attributing the deaths of shrimps to CO2 OD.

Believe me, it'll take quite a fair bit of CO2 to actually kill your shrimps. Fishes like swordtails and mollies were reportedly able to withstand CO2 concentration up to 800ppm.

For me, I've had about pH of 6.1 and kH of 4 at one stage, which would give me a CO2 reading of 95ppm. Nothing happened to my yamatoes and my apisto bred, which was my objective.

At the present moment, I'm maintaining my CO2 concentration consistently at 60-65 ppm throughout.

Kenny, have you confirmed that your pH of 6.1 is from CO2 and not any other acid buffer like the soil? What I did was to test the pH, note the reading, collect a sample of water, agitate it vigorously to dispel the CO2, store for a few hours and test again after the CO2 has escaped. I find that my second pH reading can be as much as 2.5 points higher! That's a lot of CO2, but it still means nothing if the Oxygen content is unknown.

What I'm interested in getting based on my observations through last night is how to get in more O2 without resorting to the airstone. You see, my plants don't seem to produce much O2, strange as it seems, although they are growing quite quickly.

[hobbit6003]

Hi Lawrence,

Yes, I can confirm that, as my tapwater pH is around 7.0, and I've got nothing in the tank except for some old driftwood and therefor the organic acid leach should be insignificant.

Btw, the dissolve O2 concentration is independent of the dissolved CO2 concentration. It doesn;t mean that if you have a high CO2, then your O2 is low.

The only way you can try to quantify your O2 concentration in your tank, would be to use an accurate test kit to do that.

I don't understand about the part that your plant don't seem to be producing enough O2. How do you know that? Are your fishes gasping? No pearlings?

I'd think that if your fishes are showing signs of respiratory distress, they are probably consuming more O2 than the plants can produce, which means that you've probably overstocked.

Cheers,

Kenny

[GaspingGurami]

Hi Kenny,
[quote:75629c9091="hobbit6003"]Btw, the dissolve O2 concentration is independent of the dissolved CO2 concentration. It doesn;t mean that if you have a high CO2, then your O2 is low.[/quote:75629c9091]
True, one can have both high CO2 concentration together with a high O2 saturation and have the fauna living in there happily. However, one cannot have even medium levels of CO2 (say 25ppm) if there is insufficient dissolved O2 in the tank as its inhabitants will asphyxiate, from lack of gas exchange.

[quote:75629c9091="hobbit6003"]I don't understand about the part that your plant don't seem to be producing enough O2. How do you know that? Are your fishes gasping? No pearlings?[/quote:75629c9091]
1) no pearling
2) Last month, fish gasping in the morning. But having weeded out the weaker ones, the remaining fishes have acclimatised well to this shortage of O2 and are not gasping at the surface anymore. However, one can tell that there still is O2 shortage as they are breathing very heavily until the lights come on for O2 to be made.

Actually, my plants used to pearl so much that the tank looks like a 7-up drink. Unfortunately, after a dosing accident, my plants never quite recovered. They would pearl for a day or two then stop. This is in spite of me keeping up the dosing daily!

[quote:75629c9091="hobbit6003"]I'd think that if your fishes are showing signs of respiratory distress, they are probably consuming more O2 than the plants can produce, which means that you've probably overstocked.[/quote:75629c9091]
I agree that I have an overstocked tank. I also have an over densely planted tank. Prior to my earlier mentioned dosing accident, I had even more inhabitants and only slow growing plants, in spite of this, all were living in equiblibrium. Now after the accident, I have halfed my bioload, doubled my plant load with fast growing stem plants and watersprite, and the O2 level is still so poor.

[hobbit6003]

Hi Lawrence

One thing that we should never forget is, that both plants and fishes do respire throughout the day.

However, when the lights go off, then respiration of the plant becomes more obvious, as now O2 gets consumed while none is being photosynthesized.

That is why even in ponds when they are choked full of weeds, fishes would be found nearer to the surface of the water near/at dawn, before the sun comes out.


Hmm....what did you overdose?

Kenny

[GaspingGurami]

[quote:12273e1f06="hobbit6003"]Hmm....what did you overdose?[/quote:12273e1f06]

KH2PO4. Miscalculated by 2 decimal points. so instead of adding 0.6ppm, I added 600ppm

I agree about your point on plants respiring even during daytime. However, that still does not account for why they pearl erratically, despite having no element in short measure.

[hobbit6003]

Hi Lawrence,

Wow, that's really off the tangent!!!

My guess is that the OD of PO4 would probably compromised on the health of plants, and thus they're not photosynthesizing well, and hence that caused fishes to suffer from oxygen depletion, despite the same bioloading.

My take on this, and I presume that the OD had been rectified, is to restock the tank with healthy plants.

As for the fish, I'm afriad that you might just want to reduce the fish load in there for the time being, or you'd have to use an airstone to aerate, should respiratory distress is apparent.

Cheers,

Kenny

[GaspingGurami]

Hi Kenny,
[quote:0a8de47dc7="hobbit6003"]
My guess is that the OD of PO4 would probably compromised on the health of plants, and thus they're not photosynthesizing well, and hence that caused fishes to suffer from oxygen depletion, despite the same bioloading.[/quote:0a8de47dc7]
Yep, probably what happened is as you surmised. It is a good lesson (but a painful one) in nutrient deficiency symptoms.

[quote:0a8de47dc7="hobbit6003"]My take on this, and I presume that the OD had been rectified, is to restock the tank with healthy plants.[/quote:0a8de47dc7]
Yes, I have replaced the weakened slow plants with fast stem plants and watersprite. I am however planning to slowly replace them with some "not so fast" growers, so that I dun have so much problem trimming and giving away the cuttings.

[quote:0a8de47dc7="hobbit6003"]As for the fish, I'm afriad that you might just want to reduce the fish load in there for the time being, or you'd have to use an airstone to aerate, should respiratory distress is apparent.
[/quote:0a8de47dc7]
I am on the verge of persuading the "powers that be" to accommodate a 4ft tank. This will ease the bioloading a lot. Meanwhile, I have to make do with airstone and get the plants to co-operate.

I currently share the tank with my GF. Plants and algae crew are mine, the decorative fauna are hers. Therefore, it's a bit difficult to persuade her to "get rid of" some of her "pets" while I get to keep my "ugly brown fish".

I have sorted the algae problem at least. the tank walls stay clean, and no new growth is spotted. But I just can't bear to see remnant algae especially the BBA kind sitting anywhere, especially not in the foreground under the tennelus.

[stormhawk]

Hi Lawrence,

Just my views, you're better off with Malayans if they're that hardy in your tank. I have several that are major survivors but every now and then one or two will conk out for no apparent reason. As long as conditions are not to the shrimp's liking, they'll die off pretty quick. Its usually high temperatures. At tank temperatures above 28 degC, most shrimp will conk out except those from tropical climates like the Malayans. I've lost countless batches of Tiger and Bee shrimp when the temperature hit 29+ degC. Certainly not the water because the Malayans in the tank survived but never produced eggs. pH of my tank was somewhere around 6.0 - 6.4 the last time I measured. No trace of nitrite or ammonia and a slight reading for nitrate. Normal to me but I do water changes every alternate week. The flora and fauna seem none the worst.

With BBA, I've had good luck using ramshorn snail, but as always, be wary before adding any snails to a tank. I've had several that'll eat neat little holes into pockets of the BBA when they get hungry. None of my other fish will eat the BBA. If its possible try manual removal of the BBA. If not then your algae crew need to work double hard. Sometimes Malayans will consume a little of it but never enough to kill it off. For now, just aerate the tank with a strong airstone at night, control feedings and check your shrimp for fatalities. They're the best indicators that something's wrong with the water.

With regards to the Yamatos, when you pack them at the LFS do they get something like a piece of filter floss for them to cling on? I've not had any casualties when they had something to cling on during transit but I've lost many shrimp when they didn't have something to cling on. Without the place to cling on, they get pretty disorientated and stressed quite quickly. Not a good thing for a shrimp to be experiencing. Its like putting youself in a tumbler and shaking it. Just a tip.

[GaspingGurami]

Hi stormhawk,
[quote:cf48d50260="stormhawk"]Just my views, you're better off with Malayans if they're that hardy in your tank. I have several that are major survivors but every now and then one or two will conk out for no apparent reason. As long as conditions are not to the shrimp's liking, they'll die off pretty quick. Its usually high temperatures. At tank temperatures above 28 degC, most shrimp will conk out except those from tropical climates like the Malayans. I've lost countless batches of Tiger and Bee shrimp when the temperature hit 29+ degC. Certainly not the water because the Malayans in the tank survived but never produced eggs. pH of my tank was somewhere around 6.0 - 6.4 the last time I measured. No trace of nitrite or ammonia and a slight reading for nitrate. Normal to me but I do water changes every alternate week. The flora and fauna seem none the worst.:[/quote:cf48d50260]
I think I can now confirm the cause of shrimp fatalities in my tank to be lack of O2. Ever since I have run an airstone for the times when the lights are off, I have managed to keep my latest batch of Yamatos alive for 6 days and counting

Now that I think I can safely say I've established the cause of my shrimp fatalities, and found a way to fix it, I think I'll get me a bunch of Malayans. They're cheaper, IME more effective against BBA than the yamatos I now have, and most fun of all, they're like a lie detector test -- you can tell what they have been eating by its colour

WRT high temperatures, I heard from a LFS last night that Cherry shrimps are the most adaptable, and will thrive even in 32degrees. He convinced me to buy 2 to try out in my tank. I'll report on it's progress.

[quote:cf48d50260="stormhawk"]With BBA, I've had good luck using ramshorn snail, but as always, be wary before adding any snails to a tank. I've had several that'll eat neat little holes into pockets of the BBA when they get hungry. None of my other fish will eat the BBA. If its possible try manual removal of the BBA. If not then your algae crew need to work double hard. Sometimes Malayans will consume a little of it but never enough to kill it off. For now, just aerate the tank with a strong airstone at night, control feedings and check your shrimp for fatalities. They're the best indicators that something's wrong with the water.:[/quote:cf48d50260]
I've got lots of tiny snails in my tank. They look like minature ramshorn, but they never grow larger than a shell diameter of 2mm. I've left them very much unchecked, and their population self regulates to the amount of green algae available. I've not notice them ever interested in BBA. It seems almost nothing is anyway,

[quote:cf48d50260="stormhawk"]With regards to the Yamatos, when you pack them at the LFS do they get something like a piece of filter floss for them to cling on? I've not had any casualties when they had something to cling on during transit but I've lost many shrimp when they didn't have something to cling on. Without the place to cling on, they get pretty disorientated and stressed quite quickly. Not a good thing for a shrimp to be experiencing. Its like putting youself in a tumbler and shaking it. Just a tip. [/quote:cf48d50260]
Ya, I learnt that on the first bag of yamatos I bought. I asked the LFS why he put his "rubbish" of filter wool trimming in my bag to go with the shrimps, and he told me that because the plastic is very smooth, the shrimps have nothing to cling on to and will keep swimming till they get exhausted and die. I think there is truth in that statement as I noticed that the shrimps that go swimming around and around my tank with no rest will konk out very soon.

[GaspingGurami]

Here's an update since my Monday 2 Aug posting.

1) Yamatos lived happily in my tank for a total of 7 days before dying.

2) Cherries lived two and a half days before dying together with the yamatos.

3) Mosquito shrimps was shocked by me when moulting and so died on the same day.

I am wondering why the deaths are so sudden -- they all suddenly drop down and die after swimming frantically for an hour or so, and within 24 hours, my whole population of shrimps just wiped out! Below, I'll detail what I did as well as my tank parameters when the shrimps died. Any experts, please advise me so that I won't repeat my massacre.

1/8/04
When cherries and mosquitoes added in the tank on evening of 1/8/04:
pH: 6.4, kH: 3deg , CO2: 35ppm, temp: 28deg, NO3: 10ppm, NO2: 0.2ppm, NH3: 0ppm, plants bubbling well. Yamatos have been living 5 days and feeding happily on algae. Airstone is timed to run after lights out.

2/8/04
Dosed 20 drops of LGA, top up water and added some baking soda. As holes are seen in the older leaves, dosed 30ppm potassium from K2SO4.
pH: 6.7, kH: 5deg , CO2: 30ppm, temp: 28deg, NO3: 10ppm, NO2: 0.2ppm, NH3: 0ppm, plants bubbling well. All shrimps feeding happily on algae. Airstone is timed to run after lights out.

3/8/04
0800hrs, pH: 6.9, kH: 5deg, GH: 5deg, CO2: 18ppm, temp: 28deg, Fishes and shrimps feeding happily. Water is crystal clear, algae is noticably lesser.
1015hrs, 1 cherry shrimp found dead Could it be bullying from rummynose?
Dosed 30 drops of LGA, top up water. As holes are still getting bigger in the older leaves, and the tips are yellowing, dosed 30ppm potassium from K2SO4. Fed fishes with frozen daphnia.

1045hrs, pH: 6.7, CO2: 30ppm. Shrimps swimming around and round, not wanting to settle down.

1830hrs, 1 dead yamato.

2100hrs, mosquito shrimp look dead and white, picked it up with forceps and it kicked a bit, but soon it's dead.

2200hrs When removing dead mosquito shrimp, I disturbed the other one hiding between the leaves. It started swimming frantically and turned white. Very soon, it's also dead. Spotted 2 discarded shells which look like they belong to the mosquito shrimps. pH: 6.4, CO2: 60ppm, decreased injection rate to half bubble per second. Temp: 30deg. Plants are bubbling well and in spite of high co2 level, fishes don't look like they are breathing heavily. Why do the shrimps die? Increase the aeration through the night.

4/8/04
0900hrs, pH: 7.0, kH: 5deg, CO2: 15ppm, temp: 29deg, NO3: 5ppm, PO4: 2.4ppm, NO2: 0.2ppm, NH3: 0ppm, Fe: 0.5ppm. 2 Yamato found dead. Now I have only 1 cherry and 1 yamato shrimp left.

1130hrs, time for weekly water change, 13 litres. Prepared water with aquaplus anti chlorine, baking soda to make 5deg kH, Oxycure water conditioner, 10ppm Nitrate from KNO3. When I returned to the tank, the last 2 shrimps also gave up the ghost.

Within 24 hours, my whole population of shrimps perished. To think that 24 hours earlier, they look like they are fitting in well, the cherries and mosquito shrimps are even starting to get brighter in colour. So what is the dreadful thing that has possibly caused the shrimp population to be destroyed while the fish were spared? Any kind experts willing to shed some light for me please? I really wish to have shrimps in the tank.

I can only conclude that when bad things happen to a tank, it happens with lightning speed.

[freezze]

r shrimp that difficult to kept alive.. i have 7 yamato shrimp with me for a yrs now.. n i have not change any of the water.. 2 of them also try to breed.

[Kross]

Do away with all the chemicals(fertilizers, buffers,etc...), 24hrs airstone, moderate co2, clean H2O, top up when H2O low and you might see the difference. Works for me.