PDA

View Full Version : Herbie Overflow Question


dbartkow
11/16/2011, 09:44 AM
I am looking into doing a Herbie style overflow on 110 gallon. My question is in regards to the potential of overflowing. I am going to be using a basement sump and the plumbing will need to go about 22 feet across my basement.

It seems like the Herbie goes into high flow mode once the full siphon is running. Since my plumbing is so long, is there going to be an issue with the tank overflowing before the full siphon gets going? Has anyone else tried this over such a distance? Any issues or suggestions?

Thanks,
Dave

dava6711
11/16/2011, 04:02 PM
No I wouldn't think so even with your plumbing being so long, I presume you're gonna incorporate a second standpipe that's not running full siphon? As long as you do and it's a wide diameter pipe: 1.5" or 2" you'll have nothing to worry about. Just make sure you fit both standpipes: the emergency and full siphon into the same overflow box and you'll have no problems!

dbartkow
11/16/2011, 04:42 PM
Yes I will have the full siphon pipe and the emergency pipe in the single RR overflow chamber I have. However, it is on a stock tank that has two 1" bulkheads. So that will be my smallest diameter. I can make the pipes wider, but not sure if that helps at all since the bulkheads are probably the limiting factor.

Dave

TheAquatard
11/16/2011, 08:14 PM
the length shouldn't really matter in terms of making the syphon, its all in the gate valve. The factor that the long pipes do create is that they hold alot of water. Make sure when you power off your return pump your sump can handle the excess water in the display tank PLUS all the water in the piping which will probably be pretty signficant.

dbartkow
11/17/2011, 12:19 PM
Thanks for your help!

One follow-up question. Does anyone know how much water (gph) can travel through a 1" pvc pipe and a 1.5" pvc pipe at full siphon?

Thanks,
Dave

TheAquatard
11/17/2011, 06:06 PM
I'll put it this way, on my my tank which Im using 1 inch PVC my valve is only maybe a quater of the way open. Without air entering the pipe, its going to drain as fast as gravity can pull it which would be a massive amount of water.Youre really limited by your return pump in this case, if youre looking to get the more gph. I really couldnt see you needing more than 1 inch pvc, plus its less water for the pipe to hold like i mentioned earlier.

Make you sure you got that emergency drain in there as well. My tank drains into my sump probably 97% the full syphon and 3% the emergency drain. Its impossible to match the drainage rate and the return rate so the emergency drain has to take some of the water.

One more thing! It maybe really tempting to buy a ball valve cause of the price and availbility but its not worth the head ache! Trust me from exprience spend the extra 10 bucks and get a gate valve online!

Also make sure your return line doesn't back syphon too much water into your sump.

daplatapus
11/18/2011, 12:04 AM
I have a basement dump as well and totally agree with Theaquatard. My main drain is 1 1/4" and without the gate valve it was impossible to balance. Once I replaced the ball valve with the gate, it took less than 20min. Make sure you install the gate valve down by your dump too, it works way better with the water pressure on top of it rather than the suction under it (if that makes sense)

dbartkow
11/18/2011, 10:00 AM
If you put the gate valve by the basement sump, isn't it hard to find the right adjustment since you can't see the overflow?

der_wille_zur_macht
11/18/2011, 10:11 AM
For reference, I have a 1.5" Herbie on my 360g, and a Reeflo Dart as a return pump. It probably has about 7' - 8' of head on it, so it's probably flowing around 2200 gph. With the pump wide open, the valve on the siphon is a tiny nudge from being wide open, too. So, yeah, these drains can support A LOT of flow.

TheAquatard
11/18/2011, 10:26 AM
can't help you there, its gonna take some time to set it really good, first is set your return pump to what you want your flow like, leave the full spyhon drian wide open. Run upstairs see where you're at. Ideally you want the full shyphon intake completely submerged and the emergency drian taking a small amount of water down

Don't be discouraged, the rewards are well worth the hundred trips up and down stairs

der_wille_zur_macht
11/18/2011, 10:30 AM
Another option. Put a ball valve on the bottom of the siphon line. Use it to rough-tune the drain. Put a gate valve on the return line, up near the top of the tank. Use it to fine-tune the system.

dbartkow
11/18/2011, 12:48 PM
Okay,
Thanks for all the great info everyone! So I am thinking of doing this with 1" PVC for the siphon and then 1.5" PVC for the emergency drain. Anyone see any issues with that?

The reason for the 1" siphon is to cut down on the amount of water in the pipe (over that long span) that will flow back to my sump on a power outage.

der_wille_zur_macht
11/18/2011, 12:54 PM
Should be fine. It makes sense to have the emergency larger. You'd never want your primary larger, else the emergency might not have enough capacity to keep up if the primary was blocked.

dbartkow
11/18/2011, 01:01 PM
Is there a problem with going even smaller on the siphon pipe? I know it will cut down on flow, but it sounds like most people have their gate valve more than half closed anyway.

der_wille_zur_macht
11/18/2011, 01:07 PM
The only time it becomes a problem is if your return pump is running at a higher volume than the siphon line can support. And that would be obvious (and easy to solve, by valving back the return pump).

Ideally, you'd pick a siphon line diameter that was marginally more capacity than you expected from the return pump, but many people like to way oversize things for various reasons (i.e. it gives you "more capacity" if you go to a bigger return pump in the future).

TheAquatard
11/18/2011, 05:14 PM
Id go 1 inch, how is your tank drilled?

dbartkow
11/18/2011, 06:01 PM
This must result in a lot of fast moving water pouring into your sumps. Any issues with this? How is you sump setup to handle this?

Dave

dbartkow
11/18/2011, 06:07 PM
Id go 1 inch, how is your tank drilled?

I have two 1 3/4" holes in the bottom of the tank inside the overflow chamber.

TheAquatard
11/18/2011, 06:48 PM
how big of a sump are you going to use?

dbartkow
11/18/2011, 07:45 PM
That is a good question. I was planning on using a 55 gallon for sump (protien skimmer and fuge). But I am concerned about having enough room for the water flowing back on power down. So I am considering using two 55 gallons stacked one over the other on a rack. Not sure how to organize the chambers though.

dbartkow
05/21/2012, 09:41 AM
I almost have my system ready to turn on. My 110 gallon tank is full of water (up to the overflow). The 55 gallon sump will be full of water in another day or two.

Is there any trick in starting the pump with the Herbie overflow? Do I just turn it on and let it just happen or do I have to do fill the overflow pipe first by closing the gate valve in the basement. Then turn the pump on and open the gate? I remember reading something about people almost causing a flood when the first started it. I just want to make sure that doesn't happen.

Thanks,
Dave

bdr
05/21/2012, 10:34 AM
as mentioned earlier start with you main drain wide open and SLOWLY close it. you shouldnt have an issue with it starting a siphon and overflowing when your back up is 1.5". do you fine tuning with a gate valve behind the tank so you can see the changes. again the slightest fraction of a turn may take 20 minutes to really even out. dont adjust it wait 2 minutes and adjust again let it have time to even out and readjust.