close loop bulkhead location

[JoJo]

I have a 135g tank that i will be drilling 2 holes for the closed loop returns. The tank will have dual corner overflow (with a skimmer bridge connecting them for more surface skimming). Whats the best location to place for them? The pump is a Sequence Snapper, 2400gph with 2" inlet/1.5" outlet.

I want to have 4 returns from the pump, i'm thinking of having the other 2 outlets over the top of the tank. Or do yall think its best to drill all 4 returns through the back of the tank?

 

[NATIVEVAMAN]

Two things I would like to mention first.A closed loop system is just that,it should start in the tank and end in the tank.Running a loop system through the sump will lead to flow and cavitation issues which will lead to micro bubbles in the tank.The pump for a closed loop system should not be directly in the water as they generate enormous amounts of heat.You only need one hole drilled in the tank for water supply to the pump.The returns should all go over the top.I would use 6 entry points for 2400 gph of flow with some sort of restriction on the ends of the entry points(these will give the water some some speed).If you have space I would use sweeps instead of elbows.The high flow rates tend to cause cavitation which will end up being micro bubbles in the tank.If you dont have room for sweeps use street elbows because they have rounded inside turns which will help prevent cavitation.The inside of regular elbows have squared of turns.Some form of critter protection will be needed on the intake.The hole for the intake should be below the horizontal center of the tank.This is just food for thought and I am sure I have generated far more question than I have given answers.

 

[JoJo]

Native, i guess i wrote that post kind of confusing. I spoke of the overflows just to eliminate suggestions of putting the holes too close to the outside/top of the tank. this will be a normal CLS, i'm not trying to make it in-sump. Also i want more than one inlet to the pump just in case one gets clogged.

Thanks for the suggestions!

 

[cracker]

Hey JoJo, Got any 1st round ideas yet? I only drilled drains so I want to see what You come up with for a closed loop. Consider installing the skimmer bridge 1st then see where your holes should go. The sequence pump should work great for a closed loop. The 1.5 bit is too big for returns but a couple of those would be plenty for the 2" input for the sequence. There are so many options ,it's almost impossible to decide which is best.cnfzd:

 

[JoJo]

tell me about it, it doesnt help that i'm very indecisive! i think i will only have the single corner overflow, but enlarge it. thanks for the heads up on the return size, i guess i will be ordering a diamond bit for the returns(unless i do all the returns over the back.

 

[RyanG]

I would use a dolphin pump no heat transfer at all due to seperate motor and pump housings. Thats what Ill be using on my CL

 

[JoJo]

ryan, i already have a Sequence pump which are highly rate & minimal heat transfer.

 

[RyanG]

Sorry Jojo I didnt see that until I just reread

 

[Frankie]

JoJo, did you check out my thread? what you want is what i did. If you need pictures of it look in the beginning of the thread.
I put my two top returns just under the 'trough', your (with a skimmer bridge connecting them for more surface skimming) two on the bottom and two outputs in the crnter to the pump. I hope this helps you buddy.