About 6m ago I accidentally inherited a Tiger Oscar. It's in a Juwel Trigon corner tank (fish is about 5" atm) He fed happily on defrosted prawn (as last owner specified) until about 3 weeks ago when he stopped eating and is now listless and his dorsal fin has gone raggy. There is also an upside down shark in there who has stopped eating too. The tank is kept clean and about 24 degrees but the light unit has bust and atm I cannot afford to replace it (c£90).
Any advice would be welcome. I feel if he is not happy in his environment it would be kindest to rehome but I am worried to do so now might finish him off? I hope there is something I can do to help him as clearly something isn't right as shark not eating either?
Have you got a water test kit? When's the last time you did a water change? I'm guessing you know already how big he's going to get. They are beautiful fish. What's the upside down shark, some kind of synodontis?