[uncleof6]

You have a few misconceptions here, fueled by many others sharing the same misconceptions.

First of all, what is of concern in a marine system cannot be removed by mechanical filtration. Although "protein skimming" (a misnomer) is a form of mechanical filtration, it is tasked with removing the real enemy in marine system, and that being the dissolved organics. Foam fractionation removes roughly 30% of the TOC dissolved in the water, leaving the rest to cause problems as the content builds. How well the "skimmer" works is dependent on the relative concentrations of a given constituent, flow rates (higher is better,) main tank surface skimming efficiency, and if the "skimmer" will actually remove that particular constituent or not. Assuming that the "skimmer" is going to remove most of the ****, is not realistic, and the buildup in the sponge or socks will be unaffected. They simply remove very different parts of the whole.

Particulate matter, removed by other forms of mechanical filtration (socks, mits, shoes, sponge, baseballs) are a food source for filter feeders (and other scavenger/opportunistic feeders) and are not the enemy. However, collecting such particulates within the system, contributes to the dissolved organic levels, even if only for a short time.

There are three sources of micro-bubbles in sumps: The drains, an out of proper adjustment (or low quality) skimmer, and waterfalls much over an inch high (depending on flow rates.) All of them are preventable without the need for adjunctive aids, that solve one problem, but create others.