I have a 300 gallon discus tank with about 14-15 discus 3 angels and a dozen or so tetra. I noticed that several discus, the angles and even a couple of the tetra all at the top. The look like they are trying to breath air from the top. As soon as I go near the tank they all come rushing forward, as they think I am going to feed them. But when I observe from a distance they are back at the top. They are all acting normally otherwise and eating just fine. I checked the water and all seems normal. PH 7.2-7.4, ammonia near zero, nitrites near zero, nitrates are high ~60ppm, but it usually is. I have an eheim 2262 filter. I did clean that last week and about a 75-100 gallon water change. The water temperature is about 85.7. I did move the discharge to allow more bubbles, in case there wasn't enough oxygen in the water.
Should I be worried?
Thanks in advance
Should I be worried?
Thanks in advance