Choosing a Filter
There are many different kinds of filters on the market. They all do the same things: keep the water clean for the fish, and keep the water clear, so you can see the fish. But the array of choices can be confusing to a beginning fish keeper, as various types of filters do not, in fact, do the same thing. A Under Gravel Filter is not intended to be a mechanical filter, but a biological filter. A carbon insert is designed to be a chemical filter, not a biological filter. Confused? OK, let's break this down.
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