dying cory cats

[sterczala0220]

I do not know what is going on but I can't seem to keep any cory cats alive in my tank. I got six of them last spring and they did very well for almost a year but then they all just kept on dying. My boyfriend and I bought three batches of new corries and they would all die in a day or two. The aquarium used to be planted but we switched to artificial plants because the live ones kept on dying and leaving dead leaves and gook on the bottom of the aquarium. We think that the old plant residue is what is killing our corries but we really aren't sure. It is getting ridiculous and I would like to keep some of the cute little buggers in my tank. If anyone has any advice it would be very helpful. It is just very strange what is happening.

 

[Inchworm]

Hi sterczala0220

Welcome to the forum!

It would help us greatly if you could give us some additional information about your tank and fish. Perhaps it will give us some clues about what is going on.

First, what are your ammonia, nitrite, nitrate and pH readings?

How big is your tank and what fish do you have?

What is the water temperature?

When you do water changes and bottom cleanings, how often do you do them and how much water do you replace each time?

It would also help if you put your location in your profile. Since we are an international forum, if we know where you live, we can often suggest a brand of medicine that will be available to you.

 

[GuppyDude]

beleive it or not, corys are fairly hardy, iv never had a problem with them getting sick and iv only lost 1 before. the only think i can think of that would do something like that would be something in teh water, chlorine, salt, other meds, if u specify on that stuff im sure we can have u an answer

 

[sterczala0220]

Hi sterczala0220

Welcome to the forum!

It would help us greatly if you could give us some additional information about your tank and fish. Perhaps it will give us some clues about what is going on.

First, what are your ammonia, nitrite, nitrate and pH readings?

How big is your tank and what fish do you have?

What is the water temperature?

When you do water changes and bottom cleanings, how often do you do them and how much water do you replace each time?

It would also help if you put your location in your profile. Since we are an international forum, if we know where you live, we can often suggest a brand of medicine that will be available to you.

I have a 20 gallon tank that has six tiger barbs and two powder blue dwarf gouramis along with three cory cats if they ever manage to live. The tiger barbs and gouramis are doing very well, it's just the cory cats we are having problems with. I tested my water and the nitrites are at 20 ppm, nitrates are at 0 ppm, water hardness is moderate, alkalinity and buffering capacity are in ideal range and the pH is between 7.2 and 7.6 which is in ideal range. I did an ammonia test and the results are 0 ppm which is great. The water temperature is at 80 degrees farenheit. We do water changes weekly and replace anywhere between 25% and 50% of the water. We have one of those phython clean and fill hoses where we do a bottom vacuum when we change the water. The substrate on the bottom is pool filter sand which gives the tank a very natural look. I reside in the USA in the state of massachusetts. I hope that this information will give you or anyone an idea of what is going on here. It is just very strange that the corries are all dying suddenly when we had them for about a year and they did great. It is just a mystery that I hope can be solved.

 

[Inchworm]

I tested my water and the nitrites are at 20 ppm, nitrates are at 0 ppm, .....

Hi sterczala0220

Is this what you meant to say, or did you get the figures for nitrItes and nitrAtes reversed?

 

[leedham]

i have 4 peppered corydoras and have had no problems at all i lost one to internal parasites but that got treated quickly

 

[sterczala0220]

I tested my water and the nitrites are at 20 ppm, nitrates are at 0 ppm, .....

Hi sterczala0220

Is this what you meant to say, or did you get the figures for nitrItes and nitrAtes reversed?

Now looking back at the test kit I think I did get the figures for nitrates and nitrites reversed, how silly of me. The nitrates are 20 ppm and the nitrites are 0ppm.

 

[Inchworm]

Hi sterczala0220

Darn! I knew it wouldn't be that easy!

OK, so let's look at some other things. How about the artificial plants you have in there. Could they be leaching dyes or paint or other chemicals into the water? Did the package they came in say specifically that they were for aquarium use?

Your fishkeeping routine is good, especially the water changes and tank cleanings. This is often the problem, but it shouldn't be here. Most of the time corys get sick it is due to poor sanitation and this does not necessarily show up on water tests. Since you are doing substantial water changes, this can probably be ruled out too.

However, you did mention having residue from the plants you used to have in the tank. I don't understand what you mean. Potentially harmful bacteria could grow in rotting plant debris, but with your regular cleaning routine, it should all be gone by now.

What kind of corys have you been getting? Did they all come from the same lfs?

 

[sterczala0220]

Hi sterczala0220

Darn! I knew it wouldn't be that easy!

OK, so let's look at some other things. How about the artificial plants you have in there. Could they be leaching dyes or paint or other chemicals into the water? Did the package they came in say specifically that they were for aquarium use?

Your fishkeeping routine is good, especially the water changes and tank cleanings. This is often the problem, but it shouldn't be here. Most of the time corys get sick it is due to poor sanitation and this does not necessarily show up on water tests. Since you are doing substantial water changes, this can probably be ruled out too.

However, you did mention having residue from the plants you used to have in the tank. I don't understand what you mean. Potentially harmful bacteria could grow in rotting plant debris, but with your regular cleaning routine, it should all be gone by now.

What kind of corys have you been getting? Did they all come from the same lfs?

The problem with the dying corries started way before we got rid of the real plants. The original six green corries started to die one by one and we had no idea what was going on because we take very good care of our tanks. When the green corries died, we tried some spotted ones to replace the ones that died and the same thing happened. At the time we had just six tiger barbs and two to four zebra danios. We just got the two dwarf gouramis a week ago. We tried a batch of four panda cats and they also died before we removed the last of the plants and then we left the tank bare for about a month so that the old rotting plant debris could get cleared out before we tried any more corries. You mentioned that you did not fully understand what I meant by plant debris so, I will explain better. The live plants in the tank did very well for a while but then they got covered in algae and started to die and rot. The bottom of the tank would be littered with dead leaves and gook from the algae that took over the plants. When this debris cleared up by getting sucked up by the filter and the python, that is when we put in the artificial aquarium plants. We bought them from a lfs and they used to be in our african cichlid tanks where they caused no problems. A few days ago, we bought three peppered cory cats and two of them died the next day. We still have one left but he is not very active and it wouldn't suprise me if we find him dead. It is just really bizzare what is happening to the corries because all of the other fish in the tank are doing just fine. I would think that whatever is killing the corries would also kill the other fish. I have though of one thing, the substrate in the tank is sand and maybe with the sand being much finer than gravel, some of the rotten plant debris such as roots and tiny bits we cannot see might still be in there. I hope we will be able to find the root of this problem so that there won't be anymore corries that will die. The corries we have been getting came from three different lfs. If they came from one lfs, then maybe we could say that the store could have a dirty or unkept tank. Well, we'll try to figure this one out. It looks like it may be one heck of a challenge.

 

[jhd]

sometimes it is a gravel. How large is the gravel in your tank? If you have a cloud of gunk raised from the gravel when you are cleaning it, this is what corys constantly swim in, since they are bottom dwellers. I had problems with corys till I changed to sand and in the other tank to very fine gravel, so that food could not get between stones and rot. Instead, all food is eaten if gravel is fine enough.
hth.

 

[Inchworm]

Hi sterczala0220

With the exception of the panda corys, which are difficult to keep even under the best of circumstances, the other corys should have been sturdy enough to live in your tank.

I think you might have a good point about bits of roots, etc. remaining in the sand and rotting. There is also the question of why they developed so much algae that they died.

While sand can be great for corys, sometimes it compacts and noxious gasses can form in it. This could be a factor too.

I think, before we go further, I will post in the mod's forum and see if one of the mods from the plant forum will take a look at your thread and perhaps shed some light on your situation. If the problem is related to the plants, they will know.

In the meanwhile, do you stir the sand regularly? How deep is it? Did you use any fertilizer or other chemicals to try to help the plants grow?

 

[sterczala0220]

Hi sterczala0220

With the exception of the panda corys, which are difficult to keep even under the best of circumstances, the other corys should have been sturdy enough to live in your tank.

I think you might have a good point about bits of roots, etc. remaining in the sand and rotting. There is also the question of why they developed so much algae that they died.

While sand can be great for corys, sometimes it compacts and noxious gasses can form in it. This could be a factor too.

I think, before we go further, I will post in the mod's forum and see if one of the mods from the plant forum will take a look at your thread and perhaps shed some light on your situation. If the problem is related to the plants, they will know.

In the meanwhile, do you stir the sand regularly? How deep is it? Did you use any fertilizer or other chemicals to try to help the plants grow?

When we change the water my boyfriend always gives the bottom sand a good churning. I brought up to him yesterday that maybe the sand in the tank is causing the problem because there may be leftover plant bits that we don't see. He doesn't think that is the case because when he took out all of the dying plants he gave the sand a good pythoning. He also vacuums the sand weekly and he thinks everything should be cleaned out by now. The sand is roughly an inch to an inch and a half deep. When we had the live plants, we would use a liquid fertilizer made by Nutrafin called Plant Gro which is iron enriched. The fertilizer content is 0.15 - 0 - 0. We put nothing else in the water other than start right at water changes and a little baking soda when needed for the pH.

Unfortunately the last cory cat was found dead this morning.

I hope the mod will have some useful information for the both of us. I am starting to wonder if maybe it will be necessary to change the sand. Maybe from all the plant stuff that was in there the sand may be no good. We have the same sand on the bottom of our african cichlid tanks and we have a syndontis catfish in one of the tanks where he does good without any problems. We had him for over a year and the sand does not seem to make him sick.

I don't know, maybe he is just more hardy than cory cats.

 

[Inchworm]

Hi sterczala0220

Perhaps your pH could be the problem. This is something that's usually best left alone, unless it is very high or low, or unless your fish are ones that require certain conditions. The ones you mention are in your tank are quite adaptable to a range of readings as long as it stays the same. Fluctuations in pH can cause shock and death in corys, and once you begin changing it, it's often difficult to keep stable.

What is the pH of your tap water? Do you check the pH in the bag water when you bring home new corys and acclimatize them slowly, while still in the bags, so they gradually get used to your tank water, or do you just float the bags to equalize the temperatures?

If your lfs are using the same water source as you are, they have already acclimatized the fish to it and if they are thriving in their tanks, they should do the same in yours.

Another question I wanted to ask you is if you feed frozen bloodworms?

 

[Lateral Line]

I think it is most unlikely that plant residues are the cause. When plant material breaks down, the visible "gunk" is mostly lignin and cellulose which although unsightly, is not particulaly toxic.

Something which raised my eyebrow when I read it is that you keep the tank at 80, that seems quite high to me. The warmer the water the lower it's Oxygen holding capability. Why do you have it that high?

Another issue with Corys is food. Do you feed a sinking food for them? I have found people who "can't keep Corys" were, in fact, simply starving them because they assumed there was enough flake or whatever getting down to them.

 

[Fishy411]

yeah my cories dia ll the time too. The only cories i have kept with any success at all is pandas. They lived for at least a year. whenever i buy big groups of cories they die off until theres one or two left and then the 1 or 2 survive forever.