How do I move my black moor in to a bigger warmer tank?

I have recently got a 45 gallon tank, so I could get more fancy goldfish. I was planing on getting an Oranda goldfish, but I read that they should be in warmer water such as 70-80 F. I was planing on getting a Eheim J├Ąger heater that's 125 watts for my tank. I am also wondering if it's better to have one big powered heater or two smaller heaters on both sides? But the real question is, I have a Black Moor that I didn't have heater for, so I was wondering should I put my fish in the tank then the heater or do I put the heater then the fish. If I put the fish in after how do I do so?
Asked Dec 28, 2015
No, no, cold water fish living in the 80 degree range, way too hot! Goldfish should live in water that is kept steadily in the 70-75 degree range!
Answered Feb 21, 2016

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