• Joshua448

Susan

This is just a misunderstanding; bacteria have no problem settling in a sponge, but in reef aquariums, people usually refrain from using aerobic filtration because invertebrates are quite sensitive to elevated nitrate levels. Such filters are colloquially referred to as "sponges," but this is not relevant in the case of a fish aquarium.

Tracey

Thank you. I have repeatedly read advice not to use sponges as a substrate for bacteria specifically when setting up an aquarium solely for fish with canister filters using aerobic filtration. The emphasis is placed on using bio balls, ceramics, crushed coral, and other media as substrates. Why is such advice given? Thank you.

John3142

Just sponges get clogged faster and are harder to rinse from sediment without destroying the bacterial colony, unlike ceramics.