What small fishes goes well with Beta fishes?

you can get some small corys.. corys do well with bettas.. mine are doing very well.. but i have a 29g tank ;D gets some ones like little albinos or pygmys .. good luck
 
here is a wedsite for ramshorn snails an wot is a good tankmate and also 4 litres is a rather small amount of water for a betta an a few small fish i think u should get a bigger tank for ur betta an then maybe get a few tank mates ,suitable tank mates good luck http://en.wikipedia.org/wiki/Ramshorn_snail
 
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