circulation patterns and dead spots

[clive1001blue]

Hi all, I have a 100 gallon, 6'x20"x20" with a 35 gallon sump, the 100 is drilled with a corner overflow and the sump is drilled off the side to a Little Giant 4MDQ which runs a Berlin classic above the tank. the outlets for the Berlin fill a 5 gal Carleson Surge device (assisted by a Hagen 802) which unloads every 90 seconds for about 15 seconds through a 2" pipe pointing slightly downward at the opposite end as the overflow. a bit like a forereef/backreef config. There are two other Hagen 802's in the tank for everyday circulation. My rocks are quite well spaced in an open configuration with lots of caves etc. however I'm finding lots of dead spots (as evidenced by little swirls here and there). It looks like a lot of people put a return almost as if its coming out of the overflow box, or is it my imagination? I'm not too interested in getting another power head cause I think they're ugly and with a second Carleson I would worry about overflowing the overflow. anyone have any ideas for good, thorough circulation using this equipment? If I had sand on the bottom of this tank, the surge would blow it away, it's pretty aggresive. My damn yellow tang starved itself to death :evil: thanks loads for thy input.

 

[Anonymous]

i think you are referring to a closed loop return.
the suction pipe can be routed right into the overflow box and increase overall turnover without relying on the overflow's rated GPM.

it's a great way to increase flow without cluttering the inner aquarium.

FWIW, i thinnk your tang needed proper feeding form the start.
that's just a stab in the dark.

 

[Len]

What you're describing could be a closed loop. Sometimes people also pipe their return from the sump through the overflow, so it could be that as well.

I recommend an osciallating device such as Sea Swirls. They help move water around evenly and don't exhibit the excessively strong surge problems of surge devices.