OK, I put together a web page with some pics and a quick how to on this. I will be happy to answer any quaestions.
You can see my tank here, with a link to the undergravel jet system and another special feature
or you can go right to the undergravel jet system detail here
You can see my tank here, with a link to the undergravel jet system and another special feature
or you can go right to the undergravel jet system detail here