Need Help with my snakehead

[zarliaung]

I juz got my 20 inch snakehead fish from my work. Since my workplace is relocating my manager want to release the fish. But i dont want to realease it i took it from my work. I put in my the 18inch wide, 4.5feet length and 2feet height fish tank not his old fish tank. Inside the fish tank there is two other small snakehead fish 4 inch and 8 inch long. All three snakehead fish is not eating anything at all for about 2 week since i get this fish. I dont have any experince with keeping fish and this is my first time. On the first day my colleague help me transfer the fish and help me set the water. He put aquarium salt and water conditioner, he said since singapore tap water have chlorinem, need to put aquarium salt and water conditioner. After that i put small cat fish to feed. On second day smallest snakehead fish start eating. But i nvr see medium and big snakehead fish eat. I try to put dead prawns but nobody eat. after a week later i changed water. During the process my big snakehead fish bang the glass and injure is mouth. It is about half a centimeter size. Until now the wound is reddish. The medium snakehead fish injure too at the bak area of top fin and now he could surbmerge properly and when he go down the water his tail are is curve up abit. After that i put about 10 feeding fish and 2 frog still not eating anything. I have filter put and oxygen pump put in the water. but there is no other decoration or flooring.

Please help me suggest what to do. Everyday when i see this fish i m really sad as i dont know what to do. I m clueless.

 

[bottles]

It sounds like you setup the tank and just put the fish in. If so, your filter hasn't established any beneficial bacteria yet. Do some reading on the nitrogen cycle in aquariums. You may have a lot of ammonia in your tank right now. If you know someone who has an extra filter on a tank that has beneficial bacteria, maybe you can borrow it or try to add some of the bacteria to your tank.
Snakeheads not eating when introduced to a new environment is not too big of a deal. When the large snakehead gets comfortable, the other 2 will be eaten.
Snakeheads are quite resilient and usually heal quickly from injuries, as long as the water is clean and free of ammonia and nitrite. I can't really tell from the photos if an infection is present. If there is an infection, things become more complicated.
Good luck.

 

[Brucki]

No oxygen pump needed, fish breathes air.
Do not feed ! change water more frequently, and give the fish hiding places, in a bare tank it is always stressed

 

[-DC-]

To echo much of what's been said

I agree the problem is a combination of 3 main factors , the tank is likly not cycled and ammonia is building up, a bare tank is not suitable for snakeheads , you need substrate , hides and floating cover to make them feel secure and lastly your tank is WAY too small. A tank that's 18" wide with a fish that is 20" long is simply not big enough.

And bottles is correct if/when they do settle on the larger kill and likly eat the others.

Hope that helps?