i'd also like to know what bottom feeder for a small tank.. mine is 400 X 300 and i dont think i can really put any grouping bottom feeders in it, it would just be too small.
Some Khuli loaches will do well - they get to 10 cm fully grown but they hardly ever lie in a straight line and are wonderful bottom feeders. You need a few though as they are social fish. And you must have a lid because they are jumpers. Otherwise some small corys - you will also need a few. Those are the most popular I think. Off the top of my head I cant think of any that stay small and like to be alone. Maybe a snail of some type?
Yes, I ordered about 12 of them more than 3 weeks ago; they were in quarantine - i don't think they made it.
Just a note on snails, they are all black listed, although a lot of pet shops do sell apple snails, please do not support as they are black listed!!!!
Otto's are just the best, if you buy them for work they work well, if you buy them to look at they are simply calming. It is true that a fat Otto is a happy Otto. I like the idea that one feeds them vegetable supplemental foods. I am going to try and put a stone or two in water in the sun to grow some algae for them. I am sure they will love this.