Closed Loop System

Currently my system is All-glass120 gal with a 45 gal sump. I use a Blueline 70 (1750 gph) to return water from the sump to tank. I have to use a ball value to control the flow back to main tank because the 2 predrilled over flows & an external overflow cannot handle the water volume. I was thinking of using the Blueline to make a close loop system. This would maximize the blueline & I could dissolve my powerheads. Use the 2 predrilled over flows for the sump and add a 900 gph pump for return. I would like to see if anybody has some thoughts on this or is this completely retarded! I have no experience in creating a close loop system just wait I have read. If you know any diagrams or pics for a closed loop system that would really be helpful.

Thanks

 

it seems a little strange that 3 overflows won't do 1800 gals could there be a restriction of some kind

 

It could be the fact the all 3 overflows come together to an 1" PVC that goes through the wall and into the garage where the sump sit. The maxium flow rate for 1" PVC is rated around 18GPM * 60 = 1080GPH, I believe that is under pressure. This is gravity feed, not sure what type of flow rate I'm achieving.

 

Please, be careful when you use the word "retarded." You might be offending other reefers.

 

a closed loop system is where your water from the tank goes to a external pump and then pump back to your tank to create current. In this system, if your pump for the closed loop loses its power, the water won't go anywhere.

 

It seams you answered your own question. Not enough pipe diameter for all 3 overflows. Sounds like you need to use the 1" pipe for your hob ovf and possibly plumb the internal ovf's together to an 1 1/2" diameter pipe to your sump.
Scott

 

Well, this is a commom problem with most tank today. 1" drain on everything.
I have seen 400 gallon tank with 1 1" PVC drain, and the owner wonder why they have problems. The two internal drain should be able to handle the load all you need is to split the drain to 2 1" PVC drain (I would use 2" PVC) to the sump. The bigger the pipe that faster the water drains. You don't even need the external overflow.

 

You need to get more than 1 x 1" pipe going to your sump, you will not have any problems then.

Also, most people incorrectly call it a closed loop system, it's really an open system. You are just taking the water out and pumping it right back in and they call that a closed loop.