Cory cats with fungus and platies acting odd
Hello, I have a 20 gallon tank with platies, 1 honey gourami, 1 salt and pepper cory cat (I know I should have more but I want to make sure my tank is ok before I add any) and a small pleco. My water ph is 7.4 and slightly hard. Ammonia, Nitrites and Nitrates are all fine. I recently had my water tested for drinking and everything was fine, iron was high and manganese was slightly high. I have gravel in the tank and several plants which are doing well. The tank has been up and running for about a year.
About 1 month ago I had 8 salt and pepper cories and 6 died within days of each other. It looked like it was a fungus (white and cotton like on fins) and once you saw it the fish was dead within 24 hours. I treated the whole tank but 6 of the 8 cories died. No other fish had any issues. I was planing on getting more cories once I was sure no more were sick. Yesterday one of the two remaining cories died of the same fungus. Still none of the other fish in the tank show any signs of fungus. I don’t think it has anything to do with the fungus but I did start using purigen around the time of the illness.
Another thing that is strange is that I originally purchased 6 full grown platies (2 males and 4 females) about 9 months ago. The original fish were bought at three different pet stores to make sure they were not related, so I would assume they were not all the same age. Of those 6, two females have died and the other two are starting to act strange. The two that died and the two surviving females all got very skinny, had issues with balance swimming and for the most part keep all their fins down. All other current platies look great, the older males are colorful and very active. All babies are healthy even some that are only a week old.
Since they were all full grown when I got them could they just be dying of old age?
Do female platies that give birth regularly have a shorter lifespan?
I have been concerned that I may have too many fish in my tank. I currently have 6 adult platies and 20 or so small young platies (ranging from small fry to half size). I do regular Ammonia, Nitrites and Nitrates testing. Are those the only things you need to check for when you are concerned you may have too many fish?
Any thoughts on anything I mentioned would be greatly appreciated.
Not sure if it is anything significant but most of the fish except the pleco will occasionally rub up against things in the tank. It is almost like they are itchy. This is nothing new and they do not do it very often. The fish have done this as long as I have had the tank.
Welcome to the AC.
How do you test your water?...what are your readings for ammonia, nitrIte, nitrAte, and ph?
What water conditioner do you use?
What filter is on the tank?
How often do you perform water changes, and how much water do you change?
How was the tank cycled?
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“If there are no dogs in Heaven, then when I die I want to go where they went” - Will Rogers
cories live 15-20 years of age.
what were the numbers for ammonia and nitrite? They should be 0ppm. did you test using a liquid test kit? Test strips are not accurate.
what water conditioner do you use?
what medication did you use? Not all medication works at all ph levels.
pictures would help a lot.
The rapid death and spread of the disease suggests that it is not fungus, but in fact columnaris. This is a bacterial disease that is frequently confused for fungus because both produce whitish fuzz on affected fish. What is the temperature of the tank? In my experience cories (especially ones preferring cooler water) are very susceptible to columnaris at high temperatures.
I have seen myself the symptoms you describe in your platies, but have no clue what the cause is. A female livebearer (it doesn't seem to affect male livebearers or other fish, even in a tank full of affected livebearers) will get lethargic, lose appetite, swim awkwardly with clamped fins, and progressively get more and more emaciated.
Often there also are copious amounts of stringy white excrement.
The condition seems more prevalent in crowded or unsanitary tanks. my best guess would be some kind of internal microbial infestation. Unfortunately I have not found a medication that works against this affliction, possibly because the affected fish refuse to eat medicated flakes. The only "cure" is to avoid overcrowding or abstain from livebearers altogether.
Some key things with Corydoras.
1. Sand or very fine gravel.
2. Shade and places to shelter.
3. Cycled tank.
4. More of a acidic tank.
5. Not over high temperatures.
As for some of the other fish rubbing into things sounds like the tank has some seriouse disease issues.
How often is the water changed??
Looking forward to hearing back from you regarding water testing, heating filtration, and if the tank is cycled.
Thank you for the responses. The water in my tank is 75 degrees. My ammonia is 0 ppm, Nitrites 0 ppm, Nitrates about 5-10 ppm. My ph in the tank is 7.4. I do have to treat my water to get the ph down to 7.4, it is about 7.8 out of my tap. I use liquid tests for everything and I had a local pet store check my water and their readings matched mine.
Would treating the water often with liquid ph down have any effect on the fish?
I used Microbe-Lift Artemiss to treat the tank.
Looking at pictures of columnaris I think you are correct. Sorry I can't take a picture of a fish that is sick with it because I got rid of the one that died a couple days ago. However, I guess that it is good that I currently have no fish that show any signs of it.
Your description of the platies is exactly what I have seen, I didn't notice the stringing white excrement but that is also true.
The tank is kept pretty clean. I do a 20 percent water change every week and remove all decorations and vacuum the gravel every week.
How do I know if I have too many fish? If my Ammonia, Nitrites and Nitrates are all fine could I still have too many fish?
I would like to give some of my platies to the pet store to get my numbers down, however I don't want to give them any fish that could be sick.
I have a Whisper 20 ex20 (which I am not crazy about0 with charcoal. I have a two inch plastic pipe that has a bag of puragen in it. The pipe has a bubbler on the bottom to push water through the puragen. I use Seachem Prime for a water conditioner
When I started the tank I used all old gravel that was fresh from another tank. I let the water set for a few days and then started the tank with a few fish.
Stop using PH down, it doesn't help and will make things worse if you don't understand how they affect your tap water. Platies do better with higher PH and harder water.
Last edited by Slaphppy7; 01-02-2017 at 05:40 PM.
It is strange that I had the 8 salt and pepper cory cats for about 9 months with no issues. Could I try to treat the water ph with pet moss, I have a huge piece of bog wood in the tank I thought that might help, but I haven't noticed any change. Perhaps I just have to accept that I have high PH and hard water and keep fish that do well in it.