I been noticing my 14-15" RTC has been breathing heavy lately. He has gill curl on 1 side. I also noticed he does this crazy jitter sometimes. Does anyone know what it is? I don't have airstones in my tank but I do have alot of water movement at the surface and 2 x 1200gph power heads running. I feed it about 2-3 times a week only. I do wc's twice a week. Water parameters are ammonia 0ppm, nitrite 0ppm and nitrate 40ppm.