Backyard Aquaponics
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My catfish are normally dark colored but they are turning almost white and then dying. I have done a water change and added salt with no changes.

Thanks

John

What is their behavior like? Do they act kind of spastic and jerky. Orientation problems. What's the water temperature, pH, Nitrite, Ammonia?

Could be disease, could be environment. Let us know what you've found.

Scotty
The fish are slow and not eating much at all. My water temp is 74 ph is at 6.7 ammonia is at 0 nitrates 10. I think you are right about disease. I just don't know what to do. I am setting up a second tank to get the fish out of that one.

Thanks

Johb

I had 4 do the same thing, turned light grey to white and died. I have several other species that have down just great. I give up on catfish and am doing fine with shiners and goldfish.

There are some diseases that catfish get that you really can't do much about, short of antibiotics but before you assume it's a disease check your water parameters. I think turning lighter in color is a sign of stress in catfish which can be related to environmental or disease causes. If you've had high ammonia or nitrites in the recent past this could also be the cause.

Sometimes environmental stress can cause disease outbreaks.

Sometimes it's not stress but favorable conditions for an outbreak - for example -
Temperature range is sometimes important because of stress but also because some pathogens have optimal growth at certain temps (For example Enteric Septicemia of Catfish caused by the bacteria Edwardsiella ictaluri is at it's worst between 68 and 82 F). Another disease caused by the related Edwardsiella tarda works in roughly the same temperature range. Part of E tarda's effects are caused by a haemolysin (a compound that destroys red blood cells) - the effects of the haemolysin are much worse in low iron conditions (low iron availability is fairly common in AP) http://www.cabi.org/isc/datasheet/84398.

FYI - It is possible for fish to survive these diseases and become carriers, even with antibiotic treatment which is one of the things that makes them difficult to control in the aquaculture industry. While E. ictaluri causes disease in fish, E. tarda is a generalist and causes disease in other animals including humans (though generally not as serious a disease as in fish). These bacteria are part of the Enterobacteriaceae and are related to E. coli.

I can't say you'll ever really know what caused the problems you're having with your fish but take note of some of the conditions and it may give you a better idea in the future. Look at water quality, chemistry and things like suspended solids, population density... and anything else you can think of. Sometimes taking a look at the internal organs will tell you something if there are no external signs.

I'd probably reduce or stop feeding for a while, increase aeration and salt (as you've done). It may or may not help much. If you're pretty certain it's a disease, you could spend spend some money by sending a sample to a lab for diagnostic ID of the disease and treat, if possible, based on their recommendations. This would probably cost more than your fish did

Hope this helps

P.S. - While I have some large and small catfish, I have found that Bluegill are much more durable in the conditions I have here in Oregon. Bluegill are slightly more tolerant of cool temperatures than catfish. Find what works best for you it may take some time

Scotty

Thank you so much for your reply.

John

Great info Scotty!

I just thought I might check, how much salt did you add, for how much water?

+1

Good to look at this just in case.

Thanks for all your help in this problem but it looks like it was the nitrates. The kit that I have was giving me false readings. I got a new kit yesterday and my nitrates where 80+ very high. I have the fish in a new tank until I get the nitrates down.

John