There are a couple of possibilities, the most obvious of which is our high pH. We're working on it now, but it has to be done gradually to not stress the fish too much.
Another potential killer is the light. Baby catfish usually live in the mud, out of sight and out of light.
But why are they discolored, and why are the gills red? This mysterious occurrence needs to be investigated. Join us in this bloodcurdling episode of Aquaponics Adventures!