Powerhead direction question

[mylifeismyown66]

I have had my 2 koralia 4's on each side on the back top of my tank, angled downward toward the other corner. After seeing a post on here about having them angled upward to increase exchange I was wondering if I had them in the wrong direction. Should I have them more toward the middle of the tank rather toward the top, and angled somewhat upward?

[Kdocimo90]

I have mine about 1/4 of the height of the tank, from the surface of the water angled up. I actually use 1 K4 in my 210g tank lol. I modded it with a different propeller and shaft and that thing gives out as much flow as 2 or 3 k4's combined.

[SleepyJ]

You should get plenty of gas exchange as your water flows into and out of your sump. I would keep the powerheads as is to avoid dead spots in the tank.

[mylifeismyown66]

You should get plenty of gas exchange as your water flows into and out of your sump. I would keep the powerheads as is to avoid dead spots in the tank.

Thats why I originally had them angled down. Months ago I had some slime algae on my sand and I had left them like that until today.

[Kdocimo90]

I dont think gas exchange is the issue. I have seen a presentation where they recommended the powerheads be facing the surface in order to achieve the best possible flow for your tank.

But all in all, I dont think it makes much of a difference. I would say it also depends on the corals you have (and sand!).

[mylifeismyown66]

I just took these shots from my phone, and I am still new to SPS. I know they need high flow and everything, but is this new positioning of the powerhead to direct/close to the corals or the squamosa clam I have there?
http://i46.photobucket.com/albums/f125/mylifeismyown66/0131001624.jpg
http://i46.photobucket.com/albums/f125/mylifeismyown66/0131001624a.jpg

[OK]

Pointing them straight at each other or crossing their flow creates a random flow. Just something else to consider...
Play around to see what you like. I like to hide my powerheads if I can.