need advice on drains!

[fishgate]

This is for a 120 gallon high 4 foot long tank.

I am about to get my bulkheads. I am torn between 3/4 and 1" drains (holes that I will drill). I will be going full siphon and have a jebao DC-6000 return which can push @ 1500gph. I am thinking 3/4" would be better as I think 1" would flow too much and I'd have to restrict it too much. I was thinking of two 1/2" holes for the returns.

Any opinions?

 

[Mrramsey]

I have 1" Bulkheads on my 120. It is set up with a beananimal overflow. I push about 7-800 gph through the system.

 

[iced98lx]

I would do 1 inch- easier to keep clear of blockage.

 

[Thunderfan]

You can adjust the speed of that pump with the controller. I just hooked mine up. I wish I knew how much flow it really put out because people say that 1585 its rated at is inflated. I am running it with 3/4 full blast on my 75.

 

[btucker7587]

I use dual 1.5" drains on my 150 and a herbie setup. The low pipe has restricted flow and the safety pipe is wide open.

 

[Gorgok]

You can adjust the speed of that pump with the controller. I just hooked mine up. I wish I knew how much flow it really put out because people say that 1585 its rated at is inflated. I am running it with 3/4 full blast on my 75.

It may not be inflated at no head running open, but with ~4 feet head and restricted to 3/4 pipe at least it will not be near 1500.

I have a DC12000 on my 75 with 1.5 pipe. Height over weir calculations put me over 1000 gph running on 4/6. More precise than that i can't really be sure of though.

 

[rfgonzo]

I wouldn't go any smaller then 1'' on a 120 gal drain, and 3/4'' on the return.

 

[SGT_York]

1" all around for sure.

Not sure I understand the logic of reducing the drain hole size to limit your flow??? With a siphon the pipe, size is not a contributing factor in limiting as the gate valve will be the smallest piece. (or there is no benefit in going with a smaller bulkhead) Adjusting the bulkhead size won't have any benefits. The downsides is the open channel which will be incredible noisy with a 3/4" pipe. Not to mention a serious risk if the siphon were blocked. Use a toothless weir and run a Bean Animal setup properly and let your pump run at the max. If you want to reduce the flow use the controller.

Best of luck and enjoy.

 

[fishuntbike]

I did Herbie on my 120 with 1.5 drains and 1 inch return. Really happy with the result

 

[fishgate]

OK I'm going with 1" drains and 3/4" returns. I am torn between over the back or drill 2 holes for the return. Since this is for seahorses I might just fabricate a PVC diffuser along the top going over the back. I priced out loc-line for 2 3/4" dual returns and we are talking $55 not including the bulkhead. That stuff is expensive!

 

[SGT_York]

Over the top would be my recommendation, you could just use some T's and add a few 90's to distribute the flow, provided you have a canopy top.