terrestrial mosses do decently as well. I had some extra club moss leftover from a hike collection for my terrarium, just threw it in the HOB to store it temporarily and it's gone and created a nice bio filter. In another tank, I'm using hydrocotyle in the same way. It does pretty well on my canister's outflow as well. I tried UG once but I didn't have enough and it washed away. :/
Ok, you have to share some pics!! Sounds awesome!
Gals, guys please suggest other suitable interesting plants. I love the idea of "hiding" my HOB under plants!
Let's see who does it first!