Parrot Cichlid has fin and tail rot

Question
My parrot cichlid has developed fin and tail rot that I can't figure out how to cure.I treated with melafix and then my placo developed fungus,so I treated with melafix and pimafix,but my cichlid still has fin rot and now black patches on fins and tail.I cycled the aguarium every 7 days during treatment according to directions on bottles.Should I try sulfa drugs now and how long should I wait to try something new?

Answer
Treat the water or fish with antibiotics. If added to the water, use 20 - 30 mg per liter. If the fish is to be treated add an antibiotic to the food. With flake food, use about 1% of antibiotic and carefully mix it in. If you keep the fish hungry they should eagerly eat the mixture before the antibiotic dissipates. Antibiotics usually come in 250 mg capsules. If added to 25 grams of flake food, one capsule should be enough to treat dozens of fish. A good antibiotic is chloromycetin (chloramphenicol) or tetracycline. If you feed your fish frozen foods or chopped foods, try to use the same ratio with mixing. As a last resort add at most 10 mg per liter of water. Also, if unkempt conditions are the suspected cause, correct it.