i can tell you that on my 30 gal tank i am running a cpr s50, it is supposed to do something like 300 gph, and my return pump is 500 gph so i have to tune down my return pump to keep the overflow box from getting to much air in it. so if you already have the return pump then i would get a box to match the pump
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29 gal/ 10gal refugium with more things then I have space to list.
with a 7gal sea horse tank slowly in the works |