[shaw]

Hi all,

I've been a lurker for a long time but maybe its time to come out of my shell.

For biological filtration using J-mat, Peter W recommended to go no deeper than 10 inches (or thereabouts) as its effect will be significantly compensated once the media is further submerged.

My matting is currently 18cms submerged and I can definitely see healthy biofilm on the media at the bottom. I have also seen people with very high stocking using deep filtration chambers with excellent results.

Trying to better understand where Mr W is coming from and if anyone has any experience with this?

Thank you all!