it just died today. I added 5ml of bio bacta yesterday becoz my tank was cloudy. all my other fishes r ok. I have IT. endlis. senegalus and knife fish. all r eating when I fed.
Are you're using an api freshwater test kit your nitrite color should be blue=0, ammonia yellow =0,nitrate yellow=0 you should have nitrates if your aquarium filtration is handling the bio load properly, . Cloudy water indicates bacteria bloom imo, but I will let other members chime in.
If possible take a water sample to your lfs, and let them test it for you. Purchase a API freshwater test kit, amazon may have them for a cheaper price, I personally don't like the test strips because they are hard to read.
How long has this tank be running? Cloudy water is normally a result of an ammonia spike not nitrates. ammonia spikes if the tank is not cycled or if some source overwhelms the filters like a dead fish , food waste or introduction of new fish etc. Nitrates are what comes at the end of the cycle after ammonia breaks down . It can be difficult to test for spikes in ammonia because they will come and go in an uncycled tank. Nitrates are lowered by water changes,
Channa are incredibly tollarant of poor water quality . Given the tank-mates you listed I think temperature was probably what did him in or weakened it to the point where nitrates could fininidh it off.