Closed Loop System

[amstar15]

I just bought a 150 gallon tank with dual built in overflows. the drains are 1" and the returns are 3/4".

I also want to add a closed loop system to the tank. I am going to buy diamond tip drill bits to drill the holes. I just dont know how to go about building the closed loop system. how many holes do you drill, where do you drill them (how far down in the tank compared to the top how far apart etc) what size holes do you drill

any help will be greatly appreciated.

 

[Colin_T]

if the tank already has an overflow and holes then you just connect some pipe to the holes and run them off to a sump (another tank). Then have a water pump in the sump and have some pipe going back to the main tank. You should not need to add more holes.

 

[SkiFletch]

Ummm not sure if that's what he's trying to achieve Colin.

To the OP, are you going to use a Sump, AND a closed loop?

 

[amstar15]

Yes i am going to have a 55 gallon sump with mangroves and macro-algae along with the heaters, skimmer etc. the tank is drilled on both corners with 1" drains and 3/4" returns...this will go to the sump and be returned back to tank with a genx pcx40 pump

I am looking to add a closed loop system to help generate more water flow... i want to start to get into the sps world and i do not want a whole bunch of powerheads in the tank. looking to use a snapper pump for the closed loop system

not sure what type of skimmer I am going to use yet

 

[SkiFletch]

Thats what I thought. Ok cool

You'll need a BIG bulkhead for the inlet to the snapper. Think 2" or larger. Its a good idea to look for pool inlet strainers to keep large particles out of the pump. These are usually male threaded and will fit into a bulkhead, some adaptation may be required. Usually the inlet bulkhead fitting is drilled in a place where it can be hidden from view by rocks. Then you attach that bulkhead to the inlet of the snapper via the largest pipe possible until you get to the pump where you have to scale it down (I think snappers have 1.5" fittings...). Remember to use a True Union ball valve between the bulkhead and the pump cause at some point you'll need to service the pump and you'll be ticked off if you forget that part

Then for the outlet of the CL you have coices. You can either drill more bulkhead fittings in the tank wherever you want flow to go, or you can go over the top through the canopy. It's a good idea to have multiple returns, not just one (think 4+). Since you're going SPS eventually, have you considered either an ocean motions device or perhaps a sea swirl device to create turbulent flow? Both work well with a closed loop. Again, make sure you have a true union ball valve directly after the pump outlet for when you'll need to service it.

Also consider where you want your pump to be mounted physically, keeping in mind servicability and try not to put too much torque on the bulkheads...

 

[amstar15]

Ahhh I see. So this is what I was thinking. middle of the tank about half way to a 3/4 down the tank (towards the bottom) for the inlet hole to be drilled. I was thinking at least 5 returns. two on the bottom of the tank to shoot along the back of the tank and live rock. almost straight across the back but turned just a touch towards the live rock. Then three along the top of the tank. One in the center and one at each end close to the overflow boxes.

I started to look into the oceans motion (pricey) but an option for down the road. right now I am just trying to get the just of the plumbing going then start to add more toys

the union ball valve I was going to put on the inlet piping and the return piping as well, I have heard that is a life saver.

so you are thinking the inlet drill hole needs to be big because of so much water the snapper moves??

specs on the snapper

Maximum Flow Rate: 2500gph
Maximum Shut-Off Head: 11`
Maximum Wattage: 108W
Average Wattage: 99W
Inlet/Outlet: 2" FNPT / 1.5"" FNPT
Dimensions (L x W x H): 11" x 6.57" x 7"

 

[SkiFletch]

Yes, the inlet hole needs to be big on pumps like the snapper and dart. These pumps are designed with high flow and low head pressure in mind. Ideal for closed loops, not ideal at all for sumps. My little magdrive has more head pressure capability than the Snapper . Thing is, cause they're designed for flow, not pressure, you don't want to be adding pressure drop (especially on the inlet) to the pump, cause this kills flow FAST.

That make sense?

 

[amstar15]

makes sense. would you go with a genx pump for the sump then? or go internal with a large mag drive pump?

 

[SkiFletch]

I'd totally use the external, and the genX is a great sump pump. More electrically efficient. I only use the Mag cause I didn't have room for an external

 

[amstar15]

I just got a 55 gallon tank that is set up as a refigium already. one of the baffels needs replaced (its chipped) the 55 sump is already drilled and has a 1" bulkhead on it. So its settled. I will be going with a genx pc40 I think it is for the sump and a snapper for the closed loop system.

Now on to the lights. well after I drill and plum the tank.