How do you decide placement of power heads?

[hopperjl16]

I have a biocube 29, it was recommended we add one power head. As you can see I currently have it on the back wall facing forward. Between this and the pump there seems to be a lot of flow across the front of the tank and little in the back corners. Should I move it to a side wall? It seems a lot of tanks have the power heads on the left or right wall facing in.
Thanks!

 

[hopperjl16]

Oh also, I'd eventually like to have green star polyps on the back wall which is what prompted my concern that the back wall doesn't have enough flow

 

[shollis2814]

I usually judge powerhead placement by two things: coral response and dead spots.
I have 3 powerheads plus my sump return in my 26 gallon. If corals don't like high flow, I usually tweak the powerhead versus the coral just because of how I have my corals placed. When I see red slime algae start to form, that is also usually the result of low flow.

I kinda like what you have if the current splits to both left and right as it hits the front of the tank. Drop a bit of food in front of the powerhead and see how it flows.

GSP can take a range of current, but IME look best with some moderate flow.

 

[redfishbluefish]

I'm not aware of any science on this. I placed mine where it wouldn't blow the sand and wouldn't cause waves on the surface of the water. I have a five foot tank with two powerheads on opposite sides. Both are close to middle of the tank (up and down), with the one on the left closer to the front glass and the one on the right closer to the black glass.

I like your placement with the exception of closeness to the surface....does that placement cause air being drawn in? And does it push water up the far side of the tank? If no to these questions, then you're fine.


EDIT TO ADD: Just took a second look at the picture and it looks like the powerhead is close to the saw-teeth. Will this placement keep stuff from being drawn into the saw-teeth? Maybe slide it over to the left side so the circulation pushes stuff to the saw-teeth.

 

[hopperjl16]

does that placement cause air being drawn in? And does it push water up the far side of the tank?

No air being drawn in to the power head and no waves created, surface is pretty even.

EDIT TO ADD: Just took a second look at the picture and it looks like the powerhead is close to the saw-teeth. Will this placement keep stuff from being drawn into the saw-teeth? Maybe slide it over to the left side so the circulation pushes stuff to the saw-teeth.

I think it does hinder the upper intake a little, I've definitely seen things get sucked into the intake but often they'll swirl away from it before finally going in. I certainly could move it away from the saw-teeth a little though.

I do think the overall flow is towards the front of the tank, then splits and goes to either side.

 

[cmcoker]

I have a biocube 14 setup about 4years, my buddy has a biocube 29 about same time. The star is about where we both have our powerhead. Pointing slightly up and toward the center. Has seemed to work fine.. YMMV, it depends on rock work and coral placement.