Hi sorry if I mess this up but Im new here. I have a 3+ inch 1 year old common that I have almost killed several times in my attempts to learn and be a good mom. He is currently in a ten gallon that has finally finished cycling but I am cycling a 59 gallon tank now with danios that will switch tanks once it's ready, as he has suffered enough with cycling. Can Rainbow fish and Commons get along? He used to live with a cory and frogs and they got along ok. By the way I bought two Emporer 280's for the tank which according to the petsmart employee be about right for a goldfish tank of 59 gallons. Thanks for any help.

I would not put the rainbow with the goldie. I had one with mine for awhile and he was fine for months. We went on a trip for 6 days and came back and the rainbow had beaten up one of my telescopes badly. I had to put him in my 10 with other tropicals shortly after. He has since gone to another home. The only upside is that a common is a lot quicker than a telescope but I still dont think Id chance it. Also, rainbows are tropical and prefer warmer water.

Do you know how many gallons per hour one of those filters pumps? It should say on the packaging. I am not familiar with that brand of filter. You want at least 590 gph for a 59 gallon tank. More is always better.

Oh and Welcome to Koko's!!

Each one cycles 280 gallons per hour and has extra space for additional filter media and a large bio wheel. I talked to a guy in the store he said I would need a canister as well. But the lady who works there said as long as I don't overstock it should be good. I was going to get the bigger one but it didn't cycle as much water per hour (400 total) and it was too wide for the support bars across the tank.
I also want to add plants but they said to wait until the tank is almost cycled first.

Yep the emperor 280's run at 280gph, so you've got a total of 560gph, which isn't quite up to the 10x that you'll need for a 59 gallon tank... but getting close.

You don't need a cannister for a tank that size, but it would be a great addition if you wanted to spend the money on one.

Alternately to bump up your filtration, you could add a third filter, I recommend the penguins as they come in more sizes than the emperors. You could get a 150 or a 200 and that would easily bump your capacity up nicely. I usually have three filters running on my 40.