I just did a massive trim of my tank this weekend, I have the cuttings in a bucket currently. All mosses, all mixed, all yours for free if you want them (disclaimer: the tank has BGA and snails, so would need some bucketing/treatment before using in your tank). There's a lot of weeping mosses, there might be some rose moss (but not much) and a bit of mini pelia. PM if you're interested and I can point you towards a picture of my tank so you can see the mosses (didn't want to hijack your thread with my tank pics!) I also run the double sponges in my 21L tank, usually with the outlet below the waterline. I have experimented with using an extension tube with holes in it (like a flute) above the water line, but the water pressure wasn't really enough to get the effect I was looking for, and it mostly just dripped out of the first 2 holes :)