pictures would help but I have found these to help with microbubbles in sump, just cut to fit the area and push it in. I use green as it works well and I havent had any clogging issues with it but you could go finer material depending on gph flowing through the sump. I run around 400-600gph.
Progressive density mesh mechanical filtration system can be used as a system or separately. Aquamesh #2 is great for almost all filtration applications from capturing free floating detritus to removing microbubbles. Aquamesh #2 and #3 are the most common used. Dimensions:19.5" x 24" x 1.5"...
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