gyre circulation question

[monotreme_man]

i have a flat hex 200gal tank. i have set up the water flow
as a gyre running counter-clockwise using the aquascaping
as a vertical partition down the middle of the tank. despite
using an appallingly low amount of powerheads (3 modified
mj1200s), i get good water speed and a variety of water velocities.

my main issue is that a bunch of stuff seems to get caught
floating at the water surface in the middle of the gyre.
there is really no way for it to escape and go through
the overflow box.

any suggestions?

my only thought is to periodically tunr on another powerhead that blasts
across this vortex and clear stuff out.

 

[Aqua Keepers]

I am not sure what you mean by *gyre*, but from my understanding you have all of your flow flowing in one direction creating a whirlpool effect. Is that right? If so, I suggest you rearrange the flow so it is more random.

 

[luther1200]

Or just put another PH pointing right at the problem area.

 

[monotreme_man]

<a href=showthread.php?s=&postid=15600652#post15600652 target=_blank>Originally posted</a> by Aqua Keepers
I am not sure what you mean by *gyre*, but from my understanding you have all of your flow flowing in one direction creating a whirlpool effect. Is that right? If so, I suggest you rearrange the flow so it is more random.

thats right, the water goes left to right across teh front of teh tank
and right to left across the back. (the fish have caught on to this;
if they are chasing some food across the front of the DT, they
will often cut through teh rockwork to the back and wait for the food
to appear.)

if i do random, then it will cost me $800-$1300 in powerheads
(2-3 MPW-40s or tunze equivalents). a major part of teh gyre story
is hat you can get good flow with relatively little powerhead flow.

while i don't mind the three powerheads i have now, i think i would mind
six; six would allow me to setup two gyres in opposite directions
and i could switch between them every couple of hours..

 

[sedor]

Why can't you just take one that you have in your tank now and point it the opposite direction? Its usually best to have random flow which is essentially what is happening in the ocean. Arranging the flow to create a whirlpool makes me think of a toilet being flushed.

 

[kaskiles]

If you do the random, then it sort of defeats the Gyre. They sort of explain the Gyre in terms of momentum in this article:
http://www.advancedaquarist.com/2007/1/aafeature

I'm sure there is more out in the search engines under 'reef gyre'.

Anyway, can you switch to a top / bottom Gyre instead of a front / back? That should really confuse the fish

 

[monotreme_man]

if i understand jakes correctly, then increased growth is
dependent on increased oxygen supply which is largely dependent
on water speed.

as for random flow, yes, i have see that when waves crash
on a reef, but nearly everywhere i have snorkled in a reef,
the predominant flow is tidal, often with a 2-4 knot unidirectional flow
sweeping past everything.

 

[kaskiles]

Does your vertical partition extend up and out of the water, making barrier to flow? So the food and oils and mulm accumulates up next to the partition? Or is there a small gap of water flowing over the partition? I think I'd want to try both scenarios to see which one worked.

 

[monotreme_man]

the tank looks like below. there is about 4-6in of water above the arches.
the flotsam just eddies around in a shape roughly 3ft long and about 8in wide.
(the tank is 7ft long by 2ft wide.)