Upgrading Filter To Biowheel- What Size To Get?

[trianglekitty]

I have a 20 gallon tank that came with a Top Fin 20 filter that uses a bio bag. I'm thinking of switching to a Penquin biowheel type filter. I know I should get a filter that is rated higher than my tank. Should I get a Penquin rated for 30 gallons or one rated for 50?

Also, I don't see a way to put the bio bag from the old filter into the Penquin, so should I run them side by side until the biowheel builds up some bacteria? If so, how long would that take?

Thank you!

 

[karin]

I would go with the 50 because I just do that. Really I just think that filter companies exaggerate what their filters can do so I always go way over. Yes, either transfer all your media or run side by side. If you do the transfer of media make certain to test your water daily for at least two weeks because the filter housing will contain a bit of the good bacteria and you could, again could,, have an ammonia or nitrite spike. So watch your water stats carefully. I don't have a good guess on how long the side by side method works.

 

[waterdrop]

Agree with karin, nearly always better to go bigger.