Is there any way to speed up the flow through our bulkhead fittings?

[maryc137]

I have a 140 gallon acryllic and a few days ago we removed the overflow box and drilled for two 1" bulkhead fittings. I use a Rio 3100 for a return pump and thought that I would be able to add another return pump, or maybe just get a little bigger pump. However, the water level is now running about the same as it was before and the water is at the top of the two drain holes. We were told to drill the top of the back elbow by the drain and put tubes in for air and this would speed up the drain. Tried that, but it actually slowed down the drain and the tank was dangerously full. Have now plugged those holes we drilled. My question is, Is there any way the speed up the draining? Or am I stuck with this size return pump unless we put in more or larger drains?

 

[broomer5]

maryc137
What size piping/tubing are you running from these bulkheads down to the sump ?
Can you describe the way the plumbing looks - and detail the materials used ??
If there full of water - then your stuck.
Only so much water can gavity fall down these lines.
You could increase the diameter of these lines and possibly increase the flowrate to the sump.
I'm guessing that however you have the draining lines installed, that they are not letting the water drop down fast enough.
The Rio3100 only puts out 900 gph - and two 1inch holes should be more than enough.
Are these 1" bulkheads OR did you drill 1 inch holes and use smaller bulkheads/piping/tubing ( like 3/4" ) ???

 

[maryc137]

The bulkhead fittings are the 1" ones. The hole drilled was bigger. The fitting goes into 1" inside diameter PVC and then the elbow, then into one of those flex pipes that is actually bigger than 1" because it fits on the outside of the PVC. The flex pipe goes into another 90 degree elbow at the bottom and then through the lid of the sump. We do have the pipe all the way down into the water to reduce splashing noise. Could this be slowing down the water fall?
We were sure when we did this that the Rio 3100 wouldn't keep up and we'd get another pump. Kind of disappointed that we don't need more pump because we were hoping for more water turnover so we could get rid of a couple power heads in the tank.

 

[broomer5]

Yes !!!
Having the ends of the flex line submerged can definately hinder flowrate. It can cause water to back up in the line to the depth that the sump level is at.
As example:
If you have a 8 inches of water in the sump - you'll have 8 inches of water in both drain lines. Then as the water falls down - it has to rise up a little over this 8 inch height to "push" against the head pressure in the sump. Atmospheric pressure is pushing down on the sump water level and this is what keeps the water level at the same height in the drainlines.
So the water level in the drain line must rise above this level in order for it's head pressure to push the water out.
Gravity just keeps it falling down. But head pressures allow it to flow out the ends of the hoses.
Lift up on the hose ends in the sump and let the water fall out into the sump - and get rid of that extra head pressure from the sump level side - and the water will flow out better. It has to.
Then - get ready to talk about bubbles

 

[maryc137]

The drain pipes only go about 1/2 to 3/4 inch into the water. Do you think that would make much difference if we shorten them. I'll try to pull the extension off and shorten them to see, but my husband shoved them in so I probably can't get them out. Will have to wait til he comes home from work.

 

[broomer5]

oh
I'm puzzled now too
Put on our thinking caps for this one.

 

[melbournefl]

Two thoughts, 1) increase the drain line size, go from a 1" threaded fitting on the bulkhead to 1.5 or 2 inches, but more importantly (Broomer jump in if I'm off base here) 2) the airline idea was close but I'd go to a "tee" fitting with the top of the tee pointing straight up, the side of the tee going into the bulkhead and, obviously the bottom of the tee being the return to the sump, this might cause a bit of a gurgle but we can deal with that after we get that flow rate maxed out. One other thing, Broomer, I thought that 1" gravity feed was only rated about 400GPH? Did I misunderstand something I read along the way?
Good luck and I also am putting back on the thinking cap,
Paul

 

[broomer5]

Nope Melbourne
You're probably right about that. Thanks
I'm losing my train of thought.
Matter of fact - the train pulled out hours ago - and I'm just standing here at the station looking down the tracks

 

[maryc137]

Thanks for all the replies!! My hubby and I were talking last night and wishing we had put a T instead of the elbow coming out of the bulkhead fitting. We glued the pieces so we figured we probably can't get things apart without ruining the bulkhead fittings and probably having to buy new ones. Do you think having the T up on top would really help the flow rate much? Would it be worth it?

 

[melbournefl]

LOL Choooooooo Chooooooooo I think I can, I think I can ...
Okay then, if you're running 2 1" bulkheads you *might* increase the flow by trying this ... from bulkhead 1" threaded male to 1.5" slip fitting. 1.5" slip to 1.5" tee (see my previous comments) and running 1.5" to sump. Although in theory the restriction of the 1" bulkhead will limit water flow, by increasing the return line size it *should* increase the flow. A 1" PVC line is capable of handling at least 20 GPM that is "under pressure", by increasing the pipe diameter, you're reducing your pressure loss and it may help quite a bit.
HTH keep us up to date in your testing!
Later,
Paul

 

[melbournefl]

Sorry, I was typing as you were posting ... I would certainly say that it would be worth the price of 2 new bulkheads and I'd suggest never "gluing" fittings into the bulkheads, way too limiting to future plans!
Good Luck,
Paul

 

[jester]

Just how many 90 degree elbows are there?
I used 2 45 degree bends to spread out the curve and it really seemed to help.

 

[maryc137]

We have 2 90 degree elbows on each line. Couldn't find the 45 degree ones at the store. Maybe I'll check around some more and see what I can find.
Does nobody glue their fittings? I think I'd worry about seepage if things weren't glued.

 

[jester]

I glued mine. I got my 45's at home depot. If you can't find them, I'll send you a few of you pay for the cost.

 

[melbournefl]

hello again when I suggested not gluing the fittings, I was only talking about the male threaded fittings going into the bulkheads themselves. All the other fittings should be glued, or clamped if using flex hose. The reason for not gluing the bulkhead fittings is to avoid just the situation you're in now, unable to make changes to "tweak" the system. In lieu of the glue I'd use plumbers paste to ensure a good seal at the bulkheads.
Just my .02,
Paul
::: EDIT :::
It just occured to me that they make bulkheads that use slip fittings. If you got that type, I'd suggest getting bulkheads that have FNPT to FNPT if you decide to take the old one's off and re-plumb the overflows. HTH