Yes, I have no doubt it works. Your PVC idea sounds nice as well. Just wish I could get more info in english as there parameters and type of foam seem to matter at least somewhat.

Also hard to find the right mat and a pump that has that low of a flow.

As far as the cork goes, wouldn't the mat hide all that anyhow and you just need to hide the mat? I thought putting something on the mat like that would cover the mat too much interfering with the filtration.

The most interesting aspect of the article were the statements about other filters not having much biological filtration at all...seems odd since sponge filters work so well, even ones with powerheads on them which would give a high flow rate. Not sure about canisters and power filters, but to me they seem to filter pretty well beyond just the mechanical and chemical.