am in the process of changing out all my sponge filters for Swiss Tropicals "Block" filters. I cannot get over the difference in the bubble output and efficiency. I took a few pictures today to share with everyone.
Here is a picture of the foam block. Its mounted on an unglazed tile and sinks right away.

This is the lift tube. The grey part has a piece where you attach the airline and then its sunk into the precut X in the foam. The fine holes in teh grey piece take the place of using an airstone (which always end up occluding for me) and make a great fine bubble output:

A picture of the bubble output on the new swiss tropicals filter:

Here is a picture of a proseries sponge (no lift tube, but it has the airstone....cories tend to try and spawn INSIDE the lift tube and get stuck so its been removed in this tank):

Here is a picture of the foam block. Its mounted on an unglazed tile and sinks right away.
This is the lift tube. The grey part has a piece where you attach the airline and then its sunk into the precut X in the foam. The fine holes in teh grey piece take the place of using an airstone (which always end up occluding for me) and make a great fine bubble output:
A picture of the bubble output on the new swiss tropicals filter:
Here is a picture of a proseries sponge (no lift tube, but it has the airstone....cories tend to try and spawn INSIDE the lift tube and get stuck so its been removed in this tank):