oxygenating water

Question
Sorry to bother you. I just have one quick question. I'm pretty well experienced with freshwater and brackish fish. I had just bought a magnum 220 canister filter for a 75 gallon tank. Ive read forums saying that they oxygenate water well, but some of my fish seem to be breathing kinda heavily. They are all still active and I have even put in an air pump from time to time. The water is clear as can be and the fish are very colorfull. I have knives, parrots, and other chiclids in this tank. Just need to know what u think of these canister filters and the air they provide. Thanx.

Answer
Hi Shaun;

You aren't bothering me at all. Helping you is what I'm here for. ;-)

As long as the filter makes the surface of the water move it is just fine. It doesn't have to actually make bubbles to provide oxygen. The exchange of gasses at the surface is what oxygenates the water. As the surface rotates, carbon dioxide and other gasses dissipate and air with oxygen replaces it. To increase the dissipation of harmful gasses and add more oxygen, keep air bubbles going all the time. I would check the levels of ammonia and nitrites too. If they are elevated there is too much waste in the system. Also evaluate the population and how much food you feed. Those types of fish can be pretty messy and maybe there are just too many in there.

At Your Service;
Chris Robbins