Posted: Mon Nov 03, 2008 3:28 pm
I think most people let their filters + heaters run all the time.
79 gph in a 20 gal is pretty good. That's almost 4x the water volume.
However, I'm guessing it's either a waterfall filter or an internal filter? The problem with those is that the intake and outtake are in essentially the same place. So as you are finding, near the filter is getting cleaned up, but the opposite side is not. That being said, almost all filters leave "leftovers" on the bottom of the tank. You can periodically scoop this out with either a fine net, or a turkey baster (make sure you have a designated turkey baster just for the turtles!). You could also sweep some of the bits towards the filter, to see if that helps suck them up.
For how often you clean the filter, it varies. With a smaller filter and tank, you'll probably want to do it no less than once every two weeks. You'll probably want to do a partial water change that often as well. If the water is getting icky looking, do it sooner. When you clean your filter, rinse the media in tank water, instead of tap water, so you retain the good bacteria that has been accumulated.
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