bumble bee gobies are really cool, or a koolie loach - both are bottom feeders. Depends on the size of your tank and what fish you already have. Blue Rams are quite swish. We have a pengasus in our tank - providing you have a big enough tank they are fab - but do grow very big. dwarf gouramis add some colour, or pink kissing gourami but depending on your other fish I'd avoid other types of gourami as I have found some to be a bit nasty towards other fish (mainly Golden). Or a really fab fish is the upside down catfish - it looks like it's upside down but it actually the right way up. Hope this is of some help, all the ones I've mentioned are very happy as community fish.