wow im gonna join the bandwagon and say yes your tank is on the edge of being overstocked its a little stuffy in there right now, i would like everyone esle recomend getting atleast a 10 gallon , you can pick these up at petsmart last time i got one it was about $50 for the tank, filter, heater, light, ect, everything you need. in my 5 i usualy only have 1-2 platys and maybe a corry.