Sorry it took me so long to get back, these holidays are too hectic. Thanks everybody for the help. Ok heres the answers to the questions. I have a 75 gal. with two oscars(they are still juveniles) and a pleco. For filtration I run a fluval 305, Bio wheel Emporer 280, and a Marineland Penguin 100, all of which I do run carbon in, please advise if I need more filtration because I will go buy more immediately. I know I will get scolded for this, and maybe this is my problem i dont know, but for my biological I run an undergravel with 2 large aqua clear powerheads running in REVERSE, so they push water up through the gravel and not suck all the crap into the gravel. I also run two powerheads connected to air for aeration. I change 30-40% of the water weekly religiously. My current parameters are ammonia under .02 ppm, nitrate 20 ppm, nitrite 0 ppm, ph 8, gh 180 ppm, kh 240 ppm, all of these parameters are from the tank right now, it has been exactly 5 days since the last 30% water change. Also, I feed cichlid bio gold, freeze dried krill, cichlid sticks, freeze dried meal worms, and just this week I started soaking the bio gold in liquid vitamin which I plan on doing about twice weekly, also I feed NO feeders what so ever. Thank you everyone for your help it is greatly appreciated. These oscars are very important to me and I'm not just one of those guys who abuses the fish and wonders why they are sick. Again, thank you for the help. Also, water is kept at 78-79 degrees.