I have a 3ft tank that has just cycled that has 2 angelfish, 6 glass catfish and 2 clown loaches. I am worried that the clown loaches will grow too big for the tank although the people at the pet shop tell me it will be ok? Should I take them back and get 2 bristlenose catfish instead? I also plan to put in a rainbow shark and some gouramis but am a bit confused as to how many gouramis it is safe to have in one tank and what types? please help