Channa's normal behavior is to eat less the colder the water, I wouldn't worry about that. As temperature drops, so does the metabolism. Hence why you have to feed less during winter than during summer and also need to lower the temps in the adequate seasons.the temp was a bit over 25 when i got the fish because it was over 25 in the store, and i did not want to shock it by dumping the temperature, i have turned off the heater and the room temp is 21, so hopefully it will end up around that. Its just with the full cover lid its taking a while to go down in temp, since i cant really keep it open for long periods at the time.
hopefully its the fertz i stupidly added i have used a different kind of fert before which dose not seem to bother it so i thought i would supplement it a bit, in hind sight that was stupid. i am going to keep a close eye on the fish over the next couple of days but i don't think i will dose it with and meds atleast for now while it recovers. after that i will see what happens.
i will let you guys know how the fish acts over the next couple of days, and if anybody have any more input on the thing on its tail don't hesitate to let me know. because i am still not sure what to do about it.
I wonder, though. You changed fertilizer, but did you try NO fertilizer? From my experience, plants thrive in channa tanks, because you only change water twice a year, therefore there is a build up in waste that the plants can feed on and keep going. I would try that, and only supplement if it becomes a problem rather than supplement to avoid possible problems that could not arise at all.
Chems are not mandatory, if you ask me, and should be avoided when possible.