Allthough i have never kept these fish here is a tidbit of info on them. They are bottom dwellers feeding mainly on small crustaceans, inverts, bloodworms, larvae and Zooplankton. Also they are a very hardy fish that can live in poorly oxygenated waters where as others can not live. I would suggest (if feeding this fish in captivity) to feed it a varied diet. Maybe some feeder shrimp, Bloodworms(or any type of worm would do), pellets that will sink to the bottom (they are bottom dwellers and pellets will work for food as they are nutritious and contain some extra vitamins make sure you get sinking pellets though), flake soaked in vitamins of some sort so they will sink to the bottom where this fish primarilly feeds.
Kidney beans are used to catch this fish when angling. It is a cheap trick to lure the fish in sort of like using yellow corn for mountain trout. Other than protein there would be NO other nutrient value of feeding this fish a kidney bean so try and stay away from feeding it beans of any kind as it is not a natural food source of this fish.
Hope this helps a bit.
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