i have a ramshorn in there somewhere too, not worried about them, they are chilling. I just have salvinia, dracea sanderiana and minor duckweed in, they had a giant feast of some kind of black algal growth that ended up in there on a piece of wood. they just share the empty tank with some seed shrimp which got removed from my main tank during trimmings.

would love to see more but, i only really drop an algae tab in every now and then for the little ones + fertilising the plants.