by Fuzzy on Thu May 27, 2004 5:52 pm
Saw the post a while back, since no one answered, I'll take a stab. First off I think you read about DO, which is Disolved Oxygen in water. The whole system surounding the understanding of DO in regards to fish is pretty complex. For the average aquarium owner, we know we have to airate our water, in order to introduce oxygen, as a free partical into the water. Water as we know is two atoms combined, Hydrogen, and oxygen. Fish however breath by absorbing the Disolved oxygen in water, not by breaking down the H2o. As for having too much DO, well if it got to great, the fish would not be able to swim, the water itself would lose its boyancey, and everything would sink, that is also one thought on the Bremuda Triangle loss's. Anyhow, other problems with to much DO, are related to organic matter such as algy blooms. In great concentrations, and in very poor water quality, ie organic matter left in the tank, such as dead plant material, food, even dead fish, it can cause ammonia spikes, phorphourus,Hydrogen sulfate (rotten egg smell) but your fish would all be gone to heaven, by this point. To be considered healthy, water should have a saturation level of 90% DO. Keep in mind the higher the water temp. The less DO it can hold, thus you require more airation to keep the DO level up. I don't think DO is a cause of concern in higher percntages, to fish hobbiest, however low levels are a major concern.