Plumbing overflow question

[Paul_N]

I realize when you factor in elbows for a return it reduces your return flow. My question is if you put two 90's on the overflow plumbing before it gets to the sump will if reduce the flow from the overflow? If so, is there a formula?

Thanks

 

[Paul_N]

anyone?

 

[Murfman]

Only thing I can think of is the head loss calculator; Head Loss

It isn't exactly what you asked but you could probably get close on figuring out what you need from it.

 

[eggie]

Well first thing you will need to know how much flow is passing thru your overflow box
to get a calculation wich i think is not going to be easy
Instead of using 90 why dont you use (2) 45 degres to make smoother 90

 

[Paul_N]

Well first thing you will need to know how much flow is passing thru your overflow box
to get a calculation wich i think is not going to be easy
Instead of using 90 why dont you use (2) 45 degres to make smoother 90

Will the extra 90's and 45's reduce the flow from an overflow box that is rated at say 600gph? The tank in question is a 220 that has (2) 2" bulkheads. If I ran the overflow plumbing down the side of the tank and then across the bottom would the flow be reduced from if I just ran it straight down?

 

[Murfman]

Yes it will be reduced. I run my 2" pipes down26", have a 90, taking them under the tank, then 2' to another 90 pointed to the right and then to another 90 taking it down to the sump and ending in a 45, under the water in the sump.

 

[Reeferdood]

Flow might be reduced a little but you need to make sure that your plumbing has a vent to prevent flushing. Similar to the vents that are on your sewer plumbing on your home. Use a Tee and have one end facing up to allow the air to escape..
On another note, you don't really need to have a super high turnover rate through your sump, IE don't overdrive your drains. Your filtration can only process so much at a time so no need to run too much through your filtration.. Add powerheads of some sort to your main display for more turnover.. INHO..

 

[eggie]

Will the extra 90's and 45's reduce the flow from an overflow box that is rated at say 600gph? The tank in question is a 220 that has (2) 2" bulkheads. If I ran the overflow plumbing down the side of the tank and then across the bottom would the flow be reduced from if I just ran it straight down?

You will get more reduced flow from a 90 degree elbow then using (2) 45 degress elbows to make a 90 the radio is more open ending in more flow or better yet less resistance

 

[Harry_Y]

I would assume it will have some restriction.

On my tank I ran Spa-Flex and for all the lines.

The Spa-Flex may cost more but is far easier
to work with and all my turns are very sweeping.

 

[Murfman]

You can also use a long radius 90, which is more of a sweeping curve than a striaght 90.

 

[Paul_N]

I was definitely looking into spa flex. I will probably reduce the overflow from 2" down to 1.5" or should I leave it at 2"?

 

[Murfman]

I'd leave it at 2". Reducing it to 1.5" will increase the pressure, but less flow.

 

[Paul_N]

OK thinking out loud. I have the two 2" bulkheads on the end of the tank and I am going to build an internal coast-to-coast overflow box on the end where the bulkheads are. It's a 220 so the box will be 24" wide. I don't want to drill another overflow in the end since they are 2". I like Bean's failsafe overflow. If anyone knows, what I would like to do is just have one of the 90 in the box turned down and then have the second as the failsafe and turned up. Do you think that would work? Will I get enough flow if I use just the one bulkhead? This way I can keep all my overflow plumbing 2".

 

[Paul_N]

Murfman, I love the setup you have. Very Nice! Are you still running the ATS? How efficient do you think they are compared to macro in the sump?

 

[Paul_N]

If I buy Sch 80 2" true union ball valves I have to get all Sch 80 plumbing, correct? Like bulkheads 45's and pipe? I thought I read that the Sch 80 was a different size by a fraction. Anyone know for sure?

 

[AZDesertRat]

No, the inside diameter of Sch is smaller but the OD is the same as any PVC.

 

[Paul_N]

Thanks. I don't want to use Schedule 80 due to cost. Here is my next dilemma:

I got a used 220 that is drilled for (2) 2" bulkheads. I removed the old bulkheads. Now here is my question. I do not want to go with a closed loop and a huge external pump, I want to use a submersible pump like the ATB Flowstar rated at 1500 gph. What are my options on the overflow. I have to use 2" bulkheads but do I step it down to 1.5" or just leave it with 2" plumbing all the way to the sump and also adding a 2" true union ball valve to each overflow to adjust if needed?

 

[Paul_N]

I was even looking at these and thinking about putting the ball valves on the overflow lines.

Dart Overflow Box Complete Kit - Glass-Holes.com dope aquarium stuff

 

[AZDesertRat]

You should never, never, ever restrict your overflow, let the return pump determine the overflow rate. The only reason to have valves in an overflow line is for maintenance, either completely open or completely close, no throttling. The pump determines the return rate and to some extent the level in the diplay tank along with the overflow weir or standpipe height.

 

[Paul_N]

The tank is drilled on the side. It was previously used as a peninsula tank. I will have it against a wall but still using the two holes. I was thinking about building an internal overflow box or buy the one I linked. So do you think the one I linked above from GH will work with an ATB Flowstar 1500?