this is odd

Actually, that's a very good point that Rockabillychick brought up: dead spots.

The bigger your tank the more dead spots you will have -- spots that do not get any current or are not aerated by the filter properly and therefore low in oxygen. Not good. You could use an air stone, of course, but those are noisy and the bubbles are really not small enough to help out *that* much.

Having high rated filters, or better yet, more than one filter, helps with this problem. I think most of us use two filters, one on each end of the tank, and positioned so that the flow from each does away with dead spots.

I highly recommend that anyone with a tank over 24" long run two filters, one at each end, just for this very reason.

Roan
 
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