There's no reason why you couldn't put a 6" aro in a 300g tank IMO, in fact you'd get better growth and save the hassle of having to move the fish when its bigger...
Fair point. The fact of the matter is though, that I don't have the money for a 300g. I have a job now and will be saving up monthly so that I can afford one in about a year.
What I have decided to do though is divide the 90, putting the aro, smaller sens and baby fire eel on one side and putting the weeksii, my two ropes, and my pleco on the other side till everything has grown out a bit.
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