External Overflow Box Herbie Mod

[lakee911]

Anyone have any comments about my idea to modify a hang on overflow box "Herbie" Style? There would be a gate valve below the box for adjustment and an emergecy bypass--which would require a new hole to be drilled in the box.

May try this on my system. Anyone wanna try it first?

Sketch not to scale

Think the strainer should be removed?

Thx
Jason

 

[latazyo]

yes, the last thing you need is a clog in your overflow

 

[ctreefer]

I would agree with Latazyo on the strainer. I would though cover the hole. I ended up using a piece of eggcrate to do this. My only other comment would be to if possible not join the two pipes and lower to gate valve to just above where the water enters the sump. This way the water exiting the gate valve would have a small drop to enter the sump thereby minimizing the opportunity for water noise from rushing water into the sump. Also try and angle the pipe that goes into the sump from the gate valve so the water in the pipe isn't dropping but sliding.

Here's a pic of mine. Its pretty much the same idea:

The output off of the emergency I just fitted some clear tubing that dumps into the sump.

 

[Herbie]

Yes .........its been tried before with mixed results.
It didnt work as well as a built in over flow box, simply because built in's ........"reef ready" boxes use gravity to supply water to the box. Hang on overflows must use a siphon to feed the outer box.
What a few of have found is that when the main overflow is shut off (simulating a blockage), the flow slows considerably through the siphon tube, because the emergency drain is much higher than the main drain. BUT the pump keeps pumping the same amount! The tank water starts to back-up and rise at that point.
Its easy to picture it if you look at your drawing........ The emergency drain is very close to the water level of the tank. The closer the water levels are, the slower the siphon in the overflow tube becomes. If the water levels become even between the outerbox and the tanks water level..........flow stops!
I had a Lifereef overflow box custom made by Jeff T.(the owner). There are some pictures of it in my gallery. It looked almost exactly like your drawing.........cost me a small fortune! He installed a second emergency bulkhead about the same spot your drawing has. In the end..........it worked, but I did not feel confident enough in the "safety" factor of it. It was perfectly silent.........but I just didnt trust it to keep using it. If you look at the main *old* thread ...... http://www.reefcentral.com/forums/showthread.php?s=&threadid=344892
Somewhere around pages 20-25, you will see we had some discusions about this very thing. Trying to use a hang on overflow box with this ultra quiet system. In the end we felt that it was not safe enough to use.
If you could get the emergency drain as deep in the outer box as possible..........that would be your best chance.

Note: ctreefer's design apears to be a entirely different. It is still a gravity feed box that doesnt rely on an overflow tube to feed the outer box............nice job BTW! That should work just as well as a built in factory overflow.........it has gravity working for it!

Good luck........let me know if you have any questions or need help.
Later..........Herbie

 

[lakee911]

Thanks for replies guys....and here I thought I was on to something. Hehe Best to not try it I guess.

Very nice sketch!

Thanks,
Jason

 

[ctreefer]

Thanks Herbie,

Every set up I do in the future will be using your basic idea. I've had the one shown in the picture running for over 1 year and its as silent as ever. No problems at all. When the gate valve is shut on the main drain the side overflow kicks in and does a good job of keeping up with the sump pump.

Thanks again for making my living room quiet.

 

[Aqua Keepers]

Herbie, Your thread is very long. Can you give me the cliffnote version?