You need at least 300gph running through a reactor for a tank this size.

And the rest of what Gerry said.

Regards,
Tom Barr

Thanks for the info, just want to verify since the last message that I quoted might have been confusing. I need a 300gph powerhead/flow rate for my 72 gallon tank. The way I guoted the message it may appear that I have a 180g. The company I bought from recommended 55gph. ha


Thanks

Fred