powerhead to much or not

[twogirls]

I have a 72 gallon tank and was wondering if this would be too much flow or not enough?
I have a
maxi jet 900
maxi jet 1200
Gen x 4100 in sump
I am wanting to add the new one which is a
Rio 1700 UL.
It's much bigger in size verses the maxi jet ones. Anybody have any problem with these staying suction cupped to the back of the tank?

 

[trigger11]

I could be wrong but I am starting to think the best way to think about whether or not there is enough flow is to go by the turnover rate.
My understanding is the recommended turnover rate for corals is between 20X and 30X.
This is calculated
Turnover rate (X) = GPH / Tank Size (Gallons)
So in your case
MJ 900 = 235GPH
MJ1200 = 295GPH
Genx4100 = 1085GPH
Turnover rate = 22X which would put you right there in the ballpark.
So if you added the rio 1700 you would be at 31X which should be plenty IMO. Although I am also starting to be a believer that you need a good amount of flow but each coral really needs to be in the right place. And you can tell when they are happy or not. I have only had corals for 8 months so maybe someone with more experience would disagree.

 

[twogirls]

bump