I have purchased my first sw aquarium. My set up is as follows. 75
Gallon All Glass Aquarium/ stand, drilled with overflow box. wet/dry
filter with in-sump EuroReef Es5-2 Protein Skimmer. Rio600 for pumping
water from sump back to the tank. 1 max -jet 600 powerhead (160 gph)
for circulation. 88 lbs of Fiji live rock, heater, etc. My problem is
this. The shop says the one Powerhead is enough for circulation but I
just finished reading The New Marine Aquarium and it indicates that
you need 5-10x tank volume /hr circulation through the powerheads. Who
is Right? should I get another Powerhead ?

the number of powerheads is apropreate, however you need something more powerful than a
rio600 a rio600 is good for about 200gph at 0 head (height of water from source to
destination a measure of resistance) put some difference in the two and it drops
significantly. IF you are set on rio's get the hyperflows, dont tinker with the others you
probibly wont be happy. a FOWLR does not need 10X turnover but you should get to 5X in a
pinch you can do just fine at 3X but then 75X3 = 225gph and your 600 isnt gona cut that.


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Richard Reynolds