Herbie Question?
 

Is it the gate valve on this setup that makes all the difference?
Looking at the design of the top of it in theory couldn't you cut the top off your durso and accomplish the same thing for the top?

I have a durso that comes out the back.
http://members.shaw.ca/kabong/PPs02.jpg
http://members.shaw.ca/kabong/PPs01.jpg

Would cutting off the top to let air have unrestricted flow, along with replacing my ball valve with a gate valve give me the Herbie effect?

With a Herbie the valve sits just above the sump, stricting flow into the standpipe causing the water to back up so that's all that's flowing (no air).

Doing so with only one drain would practically guarantee a flood. Why is it that you have a ball valve on there now? Restricting return flow should only be done with a back up flow.

So if there is no air intake down the drain is the GPH lower then a regular setup?

I Have a ball valve on my current setup to control flow to the refrigium
http://members.shaw.ca/kabong/sump3.JPG

As Todd said, you need two standpipes for a Herbie (primary and backup) as asking for flood without.

It's not that bulkheads flow less, just flow is balanced to return pump. Skimmin has Herbies, 2-1.5" drains, and flows ~2000gph so not like bulkheads running less (but must be closed to max'd for gravity).

I got it.
So Technically it would probably work, But I'd just be begging for a flood without a back up pipe.


According to the RC drain size calc you need a minimum 1.85" for 2000GPH Giving a difference of 1.15" So it's got a fair bit of spare.

Any one else running a Herbie setup could you give your drain size + your Aprox flow.

Yes, you can silence a single overflow pipe using a gate valve and run a Herbie using only 1 pipe. But it would be stupid.

My system uses twin Herbies (4 actual drains). Each is 1.5". Flow of about 800-1000 gph through each side.

Here's an idea that might work. Add a second overflow pipe that comes up from your primary overflow pipe that will flow if the overflow box level goes too high. In the picture below, the red dot is your gate valve. You would need to get the height of this emergency drain just right.

Call this the "Untamed" mod.
http://i142.photobucket.com/albums/r...ntalHerbie.jpg

Another modified Herbie/Durso here

That was such fun that I designed another one. This is one that could be done with a single "through the bottom" bulkhead overflow drain. It is a bit wild, but I do think it would work and be safe.


(Mind you...if something blocks your only bulkhead, you've got a problem whether you've done this mod or not!)

Untamed Mod II:
http://i142.photobucket.com/albums/r...talherbie2.jpg

untamed mod II
 

MOD II would work quite well and in fact it will be almost identical to a toilet being flushed. The siphon would be quite strong once the flow starts to go over. If you don't put a strainer on your bulkhead, i can't see too many things that can block up a bulkhead other than a plastic bag or BIG fish.

Nice work untamed. I think ill be doing this mod 2 on my build thats coming up in the next month or 2.

I think that this mod is limited in its ability to quiet things down because:

In order to have the 'back up' drain work, the top of it would have to be lower then the high water level in the skimmer box - in order for it to flow as water level rose. Meaning that you would have to have your water level in your overflow box lower then normal. Thus alot of the benefit to having a quiet drain would be removed because you would have a louder overflow.

That's true. If the water falls very far in your overflow box, it can make noise. Also, if the water falls too far, it can push air bubbles into your primary drain, which also causes noise. However, if you tune the Herbie to it's optimum, you would have the overflow box water level right at the emergency level. In fact, if some water trickled down the emergency that would be nearly perfect.

That would have the water line much higher than I've drawn it. Some testing would be required to get the emergency overflow at exactly the best height.

so is this more like what your thinking untamed?

http://i265.photobucket.com/albums/i.../Modherbie.jpg

That mod is asking for it. Snails will block bulkhead drains left, right and center.

That looks like it will work. I agree with Albert - But I think that could be overcome by a huge strainer valve. Really no Different from using only one drain and one return.

I think that this has potential to be a really good alternative for those wanting the performance of a herbie, but only have one hole drilled and have the ability to run plumbing up the back / side of the tank. However it would be very finicky and an inferior design to a herbie for a new build.

I was thinking a strainer would overcome the snails cloging up the unit as well. And yes, i know this would be an inferior design to the real herbie, but for guys like me that have a system with only one hole drilled then this "Untamed" :wink: overflow design will be better then a durso.

Yes, but you could make that emergency overflow loop even higher than you've drawn so that the water doesn't fall so far inside the overflow box.

Yes, true...but that doesn't have anything to do with the mod. If you have only one drain or bulkhead, that's always a risk. You could still apply every trick already available to prevent blockage and it would have no affect on the performance of this modified Herbie.

This is a Herbie mod for someone who wants the performance of a Herbie, yet is stuck with the limitation (and risk) associated with having only 1 drain hole.