I'll try. You want the emergency drain as high as possible, to offer maximum flexibility for the main drain to fluctuate if it needs it. You want the main drain low enough to stay submerged easily and leave that flex space between it and the emergency drain. At the same time you don't want the main drain all the way at the bottom because then you've got the whole overflow draining down into the sump in a pump-off situation. The answer to that is just have less water in the overflow, but then you'll hear the splashing of the water falling from the overflow teeth down to the water level in the bottom of the overflow itself.

That clear enough? I can try again, or use pictures if I'm talking you in circles.

no that makes sense. i'm going to try to drill tonight if i have the time. i think the overflow is going to be glass without teeth though.

I think I'm going to try a toothless overflow on the new 29. My hypothesis is toothless will be a little quieter and cause less bubbles than one with teeth, but I haven't done any research on it.

i have a toothless on my current tank and it works fine. not sure what the point of teeth are anyways.

I guess to act as a strainer.

I put a bit of 1/4"netting over my current overflow - works like a charm.

One other way that seems to work well is the glass holes 700gph kit. Obviously there is just one drain, but its super solid, I also drilled two 1" returns (which were dropped down to 3/4" for Loc Lines.

glass-holes kit is loud as hell, ime. i use one on my current tank and never could get it to quiet down.

You know what's sad... I still haven't finished the tank I was talking about in tigah's overflow diagram thread...

anyways, it looks like I'm trying to do a similar setup, but instead of using standpipes I think I'll have the overflows coming out of the back.

If you make a decision post some pics.. I'll do the same.

the bulkheads are going to be out the back of this one actually. i'll try to mock up a pic.

They're quiet if you put less than half of the recommended flow through them, but then again, almost anything is. They're quality made kits though, and you can't beat the price. I had a 2000 gph kit, with a mag3 return pump! That thing was as close to silent as any flowing water I've ever heard.

yeah, i'm running an MJ1200 as my return on my current tank, lol. mine's pretty quiet.

here's what i'm thinking. view from back of tank. holes are staggered for piping. black line is the overflow wall.

Click to view attachment

Looks good to me.

Yeah me too. thanks skillzypoo.

You're welcome, but only Lalani can call me that.

no.

Dh, nice paint skills.

lol @ "skillzypoo" I wonder who got the idea of using "poo" as a term of endearment anyways?

Here's what I did:





When I install the plumbing in the back I'll post more pics.

Dhuat, glad to see u moving right along. Been following thread because I'm planning on doing the same kind of build.
Some questions. Is that a glass overflow, and how far down from the top is it?
Also, are there other advantages to going herbie rather than gl#######s than just noise?
Thanks

Overflow is glass I painted black. It's about 1" from the top of the tank glass. i don't plan to have waves, so it shouldn't be splashing over the rim.

I went herbie because of the noise. Not sure if there are other advantages - bitts?

Wow sorry D hadn't noticed any post in here. Again sorry.

Ok that first ?

For any one followingsince while I'm late & D's already done it. Determine the needed flow. Then pick a bulkhead which will acomadate it. This be comes the backup. Place it far enough down to have some flexability in the water line. Then the main will go below it. I like to have 6-8 inch's to help adjust the flow & water lines hieght in the overflow. In my exo for exsample it needs 3" to noit suck air bubbles down. Leaving 3" to play with for noise level. I like having the water line as close to the back up/wier as posable for noise. But as skills added there's more water that will drain @ power off.


As to the wier. Smooth is what I would recomend to improve skimming. Teeth are used to keep fish from going over when the wier has to much flow per inch. Things like clowns get sucked over suprisingly easaly.




Ok big D from the pics looks perfect.oven the overflow being painted.

The other beni to the herbie besides noise is well dry floors. I know I joke about this all the time. But a single drain is just not as safe as two, & on big tanks 3(extra is used as a siphon to empty the overflow in a hurry thus no flooding) I got into the plumbin g part of the hobby cause of my wifes stippulation "if the floor ever gets wet their gone". Since back in the day my wife & sister in law were the ones that had to deal with our friends big tank exploding through the fronts bottom seem. Lol they still hold it over us. Then found I couldent sleep with the noise. So those would be the two I know of.

Thanks guys. I think ill be doing herbie in the middle of tank with two returns on the sides. Now to figure out how to make my overflow

Also bits what is and where can i get a SWDC? If i have read correctly it will split the returns about every 8 second or so

scwd

switching

current

wave

device


rate of change is based on amount of flow, along with efficiency.

Well, it's up and running. Everything works fine, except overflow box is noisy from water flowing over it and the drain keeps sucking in bubbles. Any ideas on fixing that one?

I can't remember what kind of overflow pipe you have, but one of my local Club Members fixed a noisy overflow pipe by putting resting a BioBall on top of the pipe where the water overflows.

I don't think that would work with mine unfortunately. I think what I may have to do is split the pipe to slow down the flow. It's either that, or downgrade my pump. There's just too much water flowing over that overflow, even though the drain can handle it.

Hey D
Where is the water line in relation to the weir. How close to the back up is it.

water is about an inch under the backup, probably 4-5" from the top of the weir. design flaw i think.

No should be working. Mmm

If need be put an elbow in the upper bulkhead enableing the water line to be an inch or two higher.

hey, that's smart.

I run my Herbie with just a trickle of water running quietly into the backup drain. It was too touchy to try to balance the flow and keep the water level high enough to cut the noise from the overflow.

I never have to adjust my gate valve now.

yeah, i think these two tricks combined might solve the issue

yep, now its silent. thanks guys.

Good to hear.

This thread was awesome.

So, is there, like, new pictures of this work in progress?

Dhaut, like, come over, and drill for me? Thanks.

Lol. Oh God, what did I just say?!

::

Hey DHaut, really nice job. Can you show us some more pictures of your plumbing. Also, did you end up tuning the lower drain valve (closing it down to restrict flow) so that you have water trickling through the back-up drain? Is that still silent? Does it also self-tune reasonably well if the return pump flow rate changes?

I can get some pics later. But on the other questions, yes.

Cool, appreciate it. Also, have you tried closing off the lower primary drain completely and seeing how the emergency drain handles it? I suppose there's no reason it wouldn't work because even if there's less hydrostatic pressure in the upper drain, it's also not obstructed by the gate valve like the primary drain. But I'd be curious if you've tried it.

haven't tried it, actually. i might give it a test at some point soon.