closed loop using overflow as water source

[JREEF]

My set up:
I have a 29 Gallon that I had the back of drilled. I then had a custom acrylic overflow made. The overflow is 3 sided with the three sides all 6 inches in length. The overflow goes from the top to the bottom of the tank so I have room to put rubble live rock. However, The 1 inch can not handle the flow I NOW want(mag 12).

Here's my idea.
Drill 1 inch above the bottom of overflow for 1/2 or 3/4 bulk head. Connect mag2 or mag3 in overflow to bulkhead, Then connect to a spraybar under liverock.

This should pump out about 200 or 300 gph and the rest will go down the 1 inch drain pipe to the sump.

Sorry that I have no pictures. Let me know what you think.

[wanareef]

It's been brough up before and IMO won't work - with your present overflow you are only getting about 600gals (trying to do the math with RC down on a backup) a mag 12 pumps 1200 gals - you see the problem? Not enough over flow to handle this.

Keep what you have and just add a HOB CL. I'll try and find that CL that melve did with a SCWD and pump - it just hangs on the back of the tank, no driling needed.

[JREEF]

The drilling of the overflow will not be the problem. I am just wondering if I can use the overflow which holds about 2 gallons as my source for my closed loop. I will drill the overflow if this will work and use a bulkhead to push the water into the tank.

Another problem is having the water overflow my sump the pump is turned off. My outflow hole is halfway up my tank so the tank would try to equalize and overflow my sump. Any suggestions??

[Doug1]

[quote] Here's my idea.
Drill 1 inch above the bottom of overflow for 1/2 or 3/4 bulk head. Connect mag2 or mag3 in overflow to bulkhead, Then connect to a spraybar under liverock[unquote]

Are you talking drilling the back of the tank again? or drilling into the overflow wall itself?

[electricbluelizzy]

Here is that HOB closed loop from melevsreef.com

This might help!

http://www.melevsreef.com/closedloop.html

[Doug1]

If you are going to try and pull water for your spraybar out of the overflow box, it's going to increase the amount of water that has to pour into the overflow to replace whats pulled out
increased volume can let to more noise .
As far as the sump overflowing in a power out , you have to watch the normal operating level and figure out how much water will siphon back into the sump if the pump shuts off. If the return line extends very far below the surface you need to drill a hole at the water line to break the siphon effect

[drw94]

I believe it should work as long as your overflow box can flow that much water. If I understand your correctly you will have a sump drain at the bottom of your overflow box for your sump....correct......then you will drill a hole for a bulk head through the rear wall of your over flow box and connect it to a closed loop system.....correct...... you don't have to worry about more water flowing tto your sump because of the CLS. I am planning the same thing. My tanks overflow is about the same size and it is flowing 1100 GPH through the little slot at the top, to me it seems like I could flow about 3X's that much. The only problem like Doug said before is noise.

[btang]

Originally Posted by electricbluelizzy

Here is that HOB closed loop from melevsreef.com

This might help!

http://www.melevsreef.com/closedloop.html

I used this design for my intake and it works great.