In small tanks, how to achieve high flow without direct flow?

[Kinetic]

In my 40g breeder, I had four seio 820's and a few other misc. powerheads pumping out massive flow. Then I noticed all the tissue in my sps colonies were dying closes to the powerheads, even though they were pretty darn far away. I couldn't crowd them towards the middle anymore. After replacing with all 620's all tissue has healed and they're doing much better. I'm guessing it's not a necessity to have massive flow, but then again, i do have much more crud stuck on the BB than before.

How do you get around having very direct flow, but a lot?

I like those wave2k units, they seem to displace a good amount of water for not so much money.

[DrBDC]

You now have 62X turnover in a 40 breeder if you don't have a sump w/return. That's good high flow. You did have 82X which normally shouldn't be an issue for sps, but maybe it's due to the shorter distance you have to work with. I'm running about 92X turnover and I do have to work with placment some. I was blowing the flesh off a frag of superman I glued to a tonga branch rock.

[CaptRon]

I never have any powerhead aimed at anything other then glass or surface of the water. I always bounce the flow off of something first. How close to your Seio's were the corals?

[Kinetic]

The seio's were on the side walls, and the corals about a third way over, so less than a foot. Maybe 6 - 10" away.

They weren't aimed straight at the coral either, but i'm sure it did get hit by some direct flow.

Should I just bounce all of the powerheads up to the surface first? I'm guessing doing this would avoid hitting any corals...

[DrBDC]

If all is well with the 620's now, just leave it alone.

[Kinetic]

ah, right, but I'm putting together a ~68 gallon tank soon, and I'm trying to get some ideas on how to add a ton of flow but have a fairly spaced out coral arrangement.

I guess just glass and surface bouncing is the best I can do.

[DrBDC]

On my 90 I have 2 of the high flow mjmods on opposite ends but then a couple seio 1500's in the very back corner that are out at about 45 degrees that intersect the others. Those are on the controller so it helps break up the direct hit.

[acrodave]

I have a 25 gal i have one seio 620 mj 1200 &900 and i bank them all off the glass in differnt paths

[teen]

try to keep your rock further away from the sides of the tank this way the water will have some area to calm down before actually reaching the corals.

bonucing off the glass isnt a bad idea either. ive seen a lot of tanks that have the strongest powerheads in the back corners, both facing towards the middle, front glass. this dispurses the flow so its strong, but not too concentrated.

[Kinetic]

<a href=showthread.php?s=&postid=9353565#post9353565 target=_blank>Originally posted</a> by teen
try to keep your rock further away from the sides of the tank this way the water will have some area to calm down before actually reaching the corals.

that's exactly the problem. for smaller tanks, that means a lot less room for coral... even for 3 feet long tanks, you'd basically have to put everytthing really close together in the center.

I think glass bouncing for dispersion would be best. Thanks!

[katpurdy]

flow is an issue for me too....I have a 36x18x20 tall tank...I've started collecting sps...15 so far...and find that I probably don't have enough flow...30x turn over with 1700gph...what powerheads would be the best for the dimensions of this tank? oh...and I don't want a sand storm!!