There is very little mechanical, not biological filtration. I'd compare it to a very good sponge filter or a little better under gravel filter in its ability to mechanically filter.
Aeration could use some help, you're definitely right. Here's to wondering if putting an air stone in the back compartment would help.
Actually, I could remove the old pump, use an air pump and connect it thru the old slot. My canister filter would still pull stuff through the old filter. Hmmmm.
How's that for an idea.
Sounds interesting. Take lots of pictures if you do it.
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