How much water movement, and where?

[SueAndHerZoo]

OK, so the 92 gallon is up and running and soon I hope to start stocking it with all kinds of neat livestock (fish and corals). Since I'm aiming to do everything as "right" as possible, please explain to me the theory behind water movement. Obviously I need to move water from DT to sump and back again for maintaining proper water parameters but how much "movement" do I need in the DT? I used to make sure that I always had surface agitation in my tanks (still do in the others) but do I need that surface agitation if I have a sump that has plenty? What in the DT benefits from moving water? I know you need some so that food and nutrition can come to stationary corals, but a lot versus a little is where I get confused, and, yes, I realize it depends on the individual coral. Right now I only have the two "bendy" tubes returning water to my DT and I can see movement on all the live rock in the tank. Do I need to put back in some of my powerheads or should I wait until I purchase livestock that require it?

Guidance, please?
Sue

[Fcataudo]

Depending on the corals you may need a great deal of non linear flow

[mylifeismyown66]

dead spots have a greater chance to grow algae, I do know that.

[SueAndHerZoo]

Good point - never thought of the algae factor.
Sue

[DLANDINO]

In my 46 Gallon sps tank I currently have 1640 gph in flow and am considering upping that to 2200 gph with the addition of a stronger power head. I have an area in my tank that I have a maxima clam. The clam doesn't like high flow but low and behold, in the area that the clam sits I have HA beginning to grow. So, in my opinion, the ore flow the better as long as it is not adversely affecting your animals or creating a sandstorm.

[hazmat319]

In my 75 (as was in my 90) I have a Vortech mp40 and a Koralia 2 in the DT. I have an Eheim 1260 for my return which is about 400 gph with head loss. If you have too much gph going thru your sump you have a lot of noise AND too much flow for the skimmer and fuge. So slower water movement thru the sump and then make up for it in your display. I plan to have SPS at some point so I made sure to have enough flow inside the tank.

My Vortech can give me some insane flow.....like 3000 gph or something like that! But for your 92 gallon I would put some kind of power head on each side of the tank. You definitely don't want "dead" spots where detritus builds up!

[SueAndHerZoo]

K, thanks.... I have powerheads lying around so I'll roll up my sleeves and get a couple in there and then evaluate from there.

Sue