i just bought two 3" albino channel catfish and two 4" common plecos that i put into a 29 gallon long aquarium (just a growout until i get my 100 gallon this next summer once i get my job) and i want to put something else in with them but the pet store said goldfish will kill them and i was thinking mabye get some small comet goldfish mabye a oscar? please help me out thank you very much!