Sponge filter with powerhead?

[xraycer]

Sponge filter is best run with an air pump for biological only. Running a sponge filter with a power head will clog it up quickly and shorten its life. You don't need mechanical filtration for 20L, just use the the sponge for biological and do regular WC and substrate vacuuming to accomplish mechanical.

^^^^THIS^^^^
Sponge filters are highly underrated. There are people who run entire fish rooms on air-powered sponge filters alone.
For regular w/c regimen, I will advise to aim for 50% weekly at the very minimum.........50% twice a week is even better

 

[JasonsPlecosCichlids]

I run corner matten sponges on all my tanks, two 265s, two 220 and one 75, run on air with big messy cichlids and plecos, best thing I have done to my tanks