Installed Glass-Holes 700GPH kit, overflow box is quiet, but my PVC pipe isn't..Help?

[uncleof6]

Spa flex is also a good idea. One disadvantage is you cant really press fit for experimentation. You have to glue it. 1" pipe may be better. It may be worse. It is big enough to handle the flow you are running. The pipe would be more "full" than the 1.5". You will have to experiment and see what works.

Because it is an air/water mix drain, the smaller pipe will simply increase the velocity inside the pipe, and aggravate the problem. With air/water mix drains, the larger the pipe the better. You can't beat the physics. To solve the issue, the velocity needs to be lowered, either by dropping the flow rate, or INCREASING the pipe size. Not many are willing to use 2 - 3" pipe on their systems.

Jim

 

[KromiX]

Jim, thanks so much for your help over the past 2 weeks, This is my first build and you have been tremendous help...


So, this is the idea I have going into today to quiet it down, do you think this is a good way to go about it?

Instead of starting it going straight down I put in a 45 right at the top and bring the water downward in a "S" shape?

 

[kimber45]

i would leave the 90 at the bulk head and just replace the 90's going under your tank with 45's. it may take a little experimentation to get correct length piping but judging from your pics you should have plenty of room.

 

[KromiX]

i would leave the 90 at the bulk head and just replace the 90's going under your tank with 45's. it may take a little experimentation to get correct length piping but judging from your pics you should have plenty of room.

sorry bad drawing the 90 on the top would stay, but instead of a straight drop, I make it an S shape coming down into my tank along the back of the tank...

 

[kimber45]

i think you would want to keep it as straight as possible.

the more turns the more turbulence.

if it was me i would keep the straight drop. i would cut the pipe as close to the first 90 as you can, so you keep as much length as possible. then install a 45 there followed by a short straight piece followed by another 45 then your drain piece into your sump. so really all your doing is replacing the 90's with 45's.

of coarse "mock" up your new pieces before cutting your existing to make sure they are going to fit properly.

something like this.

 

[kbb0118]

I have the same setup with elbows and such. You will probably hate this, but my noise level didn't improve until I installed a 2nd overflow (or severely restricted the output of my return pump). I have 11 tanks, and own four glass box overflows and never had a noise problem until this. GB's are generally much better at noise than regular overflow boxes. But I suppose cutting the amount of water going through each pipe in half makes it quieter? My return was drilled so I just piped that over the back and put the 2nd overflow on. I had to drain the tank which totally sucked, but I'm happy with the results. Good luck!

 

[jacksonpt]

If you're sticking with the rigid PVC (at least as a first try), do this -
glass holes box > bulkhead > 90 > pvc pipe > 45 > pvc pipe > 45 > pvc pipe

Since you're already cutting the old stuff out, I'd go right to the spa flex. In my experience, it's not nearly has difficult to work with as a previous poster made it sound. Yes, it does want to curl, but you've got the bulkhead at one end and your sump at the other end to hold it in place. Just position it so the spa flex wants to curl into the corner of the sump, not out towards the middle (and thus, up out of the water). Use zip ties or hose clamps or something to keep it in place if you need to (I have mine ziptied to one of the legs of my stand). It's easy and will give you the best results.

None of my pics show the full run, from box to sump, but you should get the idea from these 2. Click the thumbs for the bigger pics.

glass holes box is the one in the back, with the black elbow.

 

[jacksonpt]

Also, just to remind/inform people... noise can come from 3 possible places with these setups:
1) water flowing into/through the box itself
2) water flowing through the plumbing (pvc, fittings, etc)
3) water splashing into the sump

As we talk about these things, please make sure you know where your noise is coming from as the potential solutions may differ.

 

[KromiX]

So I went to home depot and bought some 1.5" spaflex, going to go straight to that since it seems like the 45's over the 90s might not do what I need as far as noise is concered. So the best way to get the shape I need with this stuff is to heat it up to lose its "coiing" tendency?

 

[KromiX]

Jacksonpt,

How did you work with the Spa Flex as far as making it the shape you wanted it to be, did you heat it up?

So with the SpaFlex is your overflow quiet and the pipes quiet?>

Also one other question, to connect the SpaFlex, there was two things I could use a PVC Coupler which had a 'collar' in the middle on the inside, and another which didn't have this, just like a short piece of PVC, whats the difference in my application and does it matter if it has the little raised "collar" in the middle?

 

[jacksonpt]

I didn't do anything special to work with it. I cut the length I needed (probably about 4' or so) and bent it back against its natural coil to keep it fairly straight while I worked with it. Then I glued it in place and zip tied it to the leg of my stand.

FWIW, I'm using 1" spa flex, so maybe it's a bit more workable than the 1.5" is, but I didn't have any problems working with it. Like I said before... I glued it such that it's natural coil pulls it towards the corner of my sump... that is more than enough to keep it in place. I only zip tied it as a precaution.

As for the noise, mine is currently VERY quiet. When standing in front of the tank, I can hear the faintest sounds of water running, but once I walk away from the tank I can't hear anything. From the beginning I've had no problems with noise coming from the plumbing. I did have A LOT of problems with noise from the box. I had to dial back my flow considerably before it quieted down. I've got a ball valve on my return that is probably only 25% open. That would mean I'm pushing roughly 175gph through the box.

 

[d0ughb0y]

Also, just to remind/inform people... noise can come from 3 possible places with these setups:
1) water flowing into/through the box itself
2) water flowing through the plumbing (pvc, fittings, etc)
3) water splashing into the sump

As we talk about these things, please make sure you know where your noise is coming from as the potential solutions may differ.

#2 is usually due to using too large pipe. this is a case where larger is not better. cavitation = noise.

1" pipe can handle 960 gph flow via gravity.
1.5" pipe can handle 2100 gph via gravity.

 

[Gtstricky]

Can you put a slight angle on your longer pipe? It is better if the water flows down the pipe instread of just dropping down.

 

[richierich2000]

does the noise sound like it get faster and slower if so that is why I put and elbo on the end of the pipe half way above the water level in the sump or I have had better luck with a tee above the water level in the sump then put a 45 pointed down.

if the tube is under the water in the sump you get air pockets and the flow is not smooth

 

[uncleof6]

***

 

[r-balljunkie]

spaflex, with a coupling connector is the easiest. 2 45's will be a PITA.

c

 

[uncleof6]

#2 is usually due to using too large pipe. this is a case where larger is not better. cavitation = noise.

1" pipe can handle 960 gph flow via gravity.
1.5" pipe can handle 2100 gph via gravity.

Yes and no. 1" pipe can handle above 1500 gph. 1.5" pipe can handle 3000 gph-- Both as siphons. With an air/water mix drain systems, for 1.5" you will have problems at right around 320 gph and up. For 1" pipe, you will start having problems probably <100 gph.

The issue with the drains is solved, when the velocity inside the pipe is low enough that the flow is laminar, (water flows along the walls of the pipe with air in the middle. As the velocity increases, either by an increase in flow rate, or a decrease in pipe size, the flow become less laminar, and more turbulent, and that is what causes the bubbles and the noise. The velocity decreases, as the flow rate decreases, or the pipe size increases.

The toilet flushing is caused by the flow rate being higher than the capacity of the air/water mix system, pushing the system towards siphon, but it cannot because of the air, but the flow rate in the pipe increases, as the head pressure increases, until it exceeds the flow rate from the pump, and then it "flushes" and starts over. The solution to that is reducing the flow rate also. Or increasing the pipe size, which will increase the capacity.

You do not go down in size, unless you are converting to a siphon system.

Jim

 

[sjm817]

IDK. I've setup up similar systems (not G-H overflow), with 1" and didn't have any problem with flow or noise in the pipes. The overflow itself and entry to the sump were always a challenge to get quiet. Flushing can be eliminated by increasing the air entry to the pipe. Do this with a big enough hole in the top of the Durso. A trick I use to eliminate the sound of the air being pulled into the Dusro is to use a 3/8" hole. Put a long length of 3/8 vinyl tubing in the hole and run it down into the stand. My Durso (dual) setup is dead silent. Mine is a RR setup, so that helps quite a bit. The Dursos are under water which quiets any noise there. The transition from the bottom of the RR is a 45 that goes to Spa Flex which drops to the basement sump. There is noise down there, but I dont care. External plumbing makes it harder since it is exposed where it can be heard.

 

[KromiX]

So what I did was cut out the 90 degree elbows and installed SpaFlex. I figured what the hell 45 degree elbows won't be as good as SpaFlex. I also angled the bulkhead elbow slightly to the left so that my water flows at an angel fluidly to the sump, NOISE IS GONE!!!!!!!!!!!!

SpaFlex is great! I bought 1.5" SpaFlex @ HomeDepot.... used the blue Rain n Shine PVC Cement for the SpaFlex and regular clear cement for the PVC side of my coupler.

Here is a picture of how it came out for people who have been following for ideas:

And Thank you everyone for your suggestions and opinions, and a special thanks to uncleof6 (Jim) who has replied with ideas and suggestions in each of my threads these last weeks on my first build, your knowledge has helped out alot, must be a great uncle to have, want a nephew?


Thanks everyone!

 

[jacksonpt]

Cool. Are you quiet now?