Rule of thumb for gph

[ryshark]

What is a good rule of thumb to figure how much water circulation you need in a reef tank? How many gallons per hour should the powerheads be putting out? NOT counting the return water from the sump. Also, should the powerheads be pointing in the same direction to have the water circulate in one direction, "whirlpool," Or is it better to point them in different directions. Thanks again, you guys are a huge help. I have a 75gallon tank and plan to stock an assortment of corals.

 

[h8z2luze]

From what i hear its better for them to be pointed in diffrent directions you dont want the whirlpool effect. You will get creative making "bank" shots and off rocks and stuff.

 

[Ziggy953]

Usually a reef has anywhere from 20-30x turn over per hour. I have about 3200gph turn over in my 72g bow. I have a closed loop that puts out about 700gph, and I have 2 Tunze 6025s that move 660gph each. My return is moving close to 1200 gph. The Tunzes are a far gentler PH and create a large swath of flow. The closed loop is plumbed through 1" pipe so it too has a larger swath of water flow.

The kind of flow you need depends on the kinds of corals you have. SPS corals like more flow where as LPS corals tend to like a little less flow.

 

[cmor1701d]

You want to have 10x - 20x tank volume of water flow from ALL sources. That includes your return pump. You want to create a chaotic water flow, not directional. The best ways to do that are to have crossing patterns or V or X patterns. Place one powerhead on the back wall of the tank in each corner. Point both towards the front center wall of the tank, or place them on opposite sidewalls pointing at each other. Any combination that causes the flow to be non-directional is good.

 

[melosu58]

It would be a good idea to have one of the PH`s pointing up gor good surface aggitation to create good aeration in your tank.

 

[jollylager]

Garf.org has a calculator for that kind of stuff. High prices on products though. Sometimes a good coral deal comes through.

 

[MT79]

should the powerheads be pointing in the same direction to have the water circulate in one direction, "whirlpool," Or is it better to point them in different directions.

You don't want laminar flow, you want turbulence. A random, chaotic flow is the most desirable. As said, just how much depends on the coral species you plan to keep. Having the PH's/pumps bounce off each other and/or the tanks walls is the easiest/cheapest way to create this. You can also look into wavemaking devices such as timers, SCWD, etc.

EDIT- Double post- Sorry Cmor1701d I missed your response on my fisrt read through. didn't realize this thread was old either-I'm going to bed

 

[cmor1701d]

NP Mike. I do that too when I'm tired. I didn't realize you were that close. I work in Princeton.

 

[MT79]

I'm about 15-20 miles outside of philly these days. Still not too far though. A little cold in these parts lately eh? lol

 

[cmor1701d]

My MH's keep it toasty inside. I'm ready to crack open a window <g>

 

[MT79]

My MH's keep it toasty inside. I'm ready to crack open a window <g>

That's true