I have important questions about filters and air stones?
I want to eventually want to get a 15 or 20 gallon tank with some fish but I have some questions about filters and air stones. What do air stones do first of all? Don’t they just add oxygen to the water? I thought filters did that too? If I do get a 15 to 20 gallon tank I will need a somewhat quiet filter? Any suggestions on that? I can’t have a filter that makes a lot of noise like the kind they creates a big waterfall.
Air stones add oxygen by circulating the water. The oxygenation happens when the surface of the water contacts the air, so the air stone increases this reaction by moving more water to the surface and down again. Filters do the same thing, because they circulate the water, so if you have a filter in a 15 or 20 gallon tank, you probably won’t need an air stone.
The type of filter that hangs on the back doesn’t make much noise if you keep the water level near the top of the tank (because the water won’t fall very far), but you can use a sponge filter, an internal power filter, or an external canister filter if you prefer. Just make sure there is some surface turbulence to move the water around. Most filters will provide this, but if you have one that doesn’t, you may want to add an air stone.