Tetras

10g is only enough room for 1 school of fish and a centerpiece type fish. I suggest choosing the Cardinals over the Rummies, as Rummies get around 2 inches and are pretty active tetras. 10g is not enough room for them IMO. Mine use up every inch of my 55g and school constantly. I'd go with 6-8 Cardinals and a Betta or Honey gourami. Its best to keep 10g tanks understocked if you can because of the small volume of water.
 
i would get EMBER TETRAS they are real cool.. pygmy size they say 1 inch but just got 20 thursday and they seem to be 2 cm.
very active and shoal very well, they are in my 90g with 30 neons and cherry barbs, female bettas, a few emperor tetras, dwarf platys, corys,clown loaches and they hold their own.. not a bit bothered by the bigger fish that want to scare them..neat..
 
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