Powerheads and flow?

[thereefer9]

I am setting up a 70 gallon reef for LPS,Sps and soft corals. How many powerheads would I need for this reef? The tank dimensions are 36x18x24 inches. How much flow do I need? I already have a Maxi jet 820 powerhead and a hang on the back refugium and coralife superskimmer.
Thanx
THEREEFER9

 

[skipperdz]

my 55g has 2 powerheads plus the over flow as a 3rd. if you angle them right youll have pretty good flow. one angled at each end should send the flow all over the tank

 

[trigger11]

Typically speaking a good way to think of water flo is water turnover rate.
Turnover rate(X) = Gallons Per Hour (GPH) / Tank Size (Gallons)
With keeping both LPS and SPS you will want to be somewhere between 25X and 30X turnover rate.
So you will want to get somewhere around 1800GPH with all of your equipment. I would recommend another 2 powerheads at least. Or could go with a sump or wet/dry filter and can get a big chunk of water movement there with the return pump.

 

[thereefer9]

do i need to turn the powerheads on at different times?

 

[rattler739]

As for turn over rate i have heard anywhere from 10 X #G's up to 30 X #G's so you would want anywhere from 700gph to 2100gph but if you want corals that need medium to good flow then i would use about 20X to 25X and then if you get a coral that needs lower flow put it in the most calm area in the tank and so on with higher flow. Just make sure you dont have any dead spots and if you get a couple of PH's I would get the kind that move back and forth to help with that.
Hope this helps.

 

[thereefer9]

would this be good postion for my powerheads 2 on the top back of the tank on opposite sides blowing water towards the front creating a swirl when it hits the glass. And 2 on the bottem blowing water behind the rock wall towards each other to keep the back circulated and to keep detritus from settling on the sand bed

 

[rattler739]

U dont want to create a whirlpool but i would put the two on top facing the frontand then two on the sides facing in and would use the ones that move back and forth to make sure there are no dead spots.

 

[thereefer9]

okay so I am planing on having around 1980 gph with 3 Azoo powerheads. Are these any good they are much cheaper.Also 1 maxi jet. Should this cover water flow for all the corals?