Plumbing help needed 120gal 2- dual overflows

[Haasume]

I have a 120 gallon pre-drilled with dual overflows on each back corner.
-Each overflow has a 1" bulkhead and a 3/4" bulkhead.
-So a total of 2- 3.4" bulkheads and 2- 1" bulkheads

This is my first build that doesn't incorporate a single drain pipe, so I was wondering if I could make a bean animal using both overflows so basically:
- In the left overflow put the first two pipes (Primary drain 1" Herbie) & ( Secondary Drain 3/4" Durso standpipe)
- In the overflow in the left corner use my (1" bulkhead as the emergency drain) & (3/4" bulkhead as the return) So basically I have a bean animal except the emergency drain is not in the same overflow.

I would have to run either the emergency drain pipe horizontally once it gets below the stand OR both the main and secondary drain horizontally in order to get them all to the same side of the sump. The tank is 72" long. Which would be better to run horizontally? I was thinking the emergency beings the return can have more horizontal runs in the plumbing without causing any problems.

Is this just a ridiculous idea? Is it even possible? Does anyone have any better suggestions on how I can plumb this. Thank you in advance for any help.

 

[mcgyvr]

http://www.reefcentral.com/forums/showthread.php?t=2595141
Watch that... do that... enjoy..

 

[Ted_C]

you'd have to tie the overflows together in the tank to get a true bean animal (so the level of the water in the two overflows is one in the same). I have a 150 with dual overflows and have two herbie styles in both.

Use the 3/4" for full siphon (with ball valves / gate valves) and the 1" as emergency overflow (no valves - completely wide open). Take each pipe seperatly to the sump. do not tie them together.

The trick is to get it dialed in such that your 3/4" is taking 100% of the flow available in both chambers without pulling air. The 1" should be dry almost all the time.

the 3/4" will be about 6" below the maximum height you want to have water in your overflow box. The 1" will be near the top of the level where you want water in your overflow box.

A good rule for these plumbing ideas: never tie two pipe's drains together - ever. It just doesn't work. You mess with the venting and siphon abilities when pipes are tied together. What might work now might not work in the future due to biofilms and maturity and algae and such gumming up the works.

 

[Haasume]

What do you do with your sump return? Do you have a 5th hole for the return or do you run it up the back with flexable tubing and go over the back side wall into the aquarium? ?

 

[Haasume]

awesome video. Thank you

 

[mcgyvr]

awesome video. Thank you

Yes it shows EXACTLY what one should do with a setup like that.. Following that will ensure success..

 

[Ted_C]

up and over for the return.

you'll probably find out you dont have the space in the overflows to make those 90 degree "reverse traps" like in the video. Mine dont have the traps - just straight pipe. The video example also has a low margin for error - if something goes wrong - you'll be overflowing your display tank. Not everyone has the exact design to ensure the pump return section runs dry before an overflow can happen.

I forgot to mention: the 3/4" - your going to want that around 6-10 inches below the level of water you want in the overflow (it should always be completely submerged). the 1" open channel needs to be about 1/2" below the maximum allowable level - it's like your emergency and should be dry almost all the time.