Elbows and pumps ?

[Agu]

I'm aware that elbows on the output side of a water pump increase head and drop pressure a lot more than straight runs or gentle curves. Is this also true on the input side of a pump? I've decided to mount my insump return pump, mag 950, externally. The sump has a 1" bulkhead and what I'd like to do is install a 1" threaded x 3/4" barbed elbow into the bulkhead and then add the pump and shutoff. This would save a lot of space in the stand and make for a cleaner installation, but my return pump is already marginal and I'm concerned about a drop in flow. If it does cut the flow will it be very much?

Agu

[Cookoopod]

Agu,

I have my GenX Mak4 mounted this exact same way. I use a 90 degree from the sump and it does save a lot of space. Unfortunately, from my hydraulics classes in college and from hydraulics in Army Engineering, I do recall that pipe fittings such as the one you mention placed before or after will affect the flow rate due to head loss.

[BRW]

No expert here, but I believe if the inlet water is free to get to the head by gravity alone you shouldn't see much change. But the inlet side definitely needs to be completely gravity fed, if any suction is required the pump probably won't start. Also, you are putting the shutoff on the outlet side right? Also a must. When you move the pump if you clean it well you may pick up some gph. I just completed redoing my sump and plumbing setup to a 150 gal. Rubbermaid stock tank. I use two LG 4MDQX-SC pumps and the built-in overflows have had no problem handling the gph for about a year. I cleaned both pumps and used flexible PVC instead of clear tubing wherever possible. Now I have to throttle back both pumps to keep the water in the tank :). JME. HTH.

[Agu]

Cookoopod,
If I could do the elbow in 1" and then reduce down would that be better? Is it worth the hassle of ordering fittings? That's what I was planning but I can't find the fittings locally.

BRW,
The valve will be before the pump as I don't anticipate using it to throttle down flow. It's there so the pump can be removed without draining the sump. I'm aware that if/when the pump is upgraded the valve for flow control needs to be upstream. There's about 8" of water in the sump above the bulkhead so gravity feed to the pump is no problem.

Agu

[dnjan]

Gravity feed or not, there will be headloss in the input pipe. Adding an elbo makes it worse. Using larger diameter helps a lot.

What will you be using for an input strainer? For in-sump pumps I have always just used the slots in the pump cover. But when I upgrade from my last remaining RIO, I won't have room to fit a new pump into the space used by the existing one. And I think I need some kind of strainer just to keep "crud chunks" as well as exiled crabs out of the pump.

[Agu]

I got lucky during lunch, with plumbing that is!! The other local hardware store started carrying 1" fittings and 1" vinyl tubing. Of course now the question is should I just replumb all the returns with 1" up to the tank bulkheads. Of course I should, but maybe another time ;).

dnjan, My sump has an acrylic barrier about 1 1/2" from the bulkhead end that's drilled full of holes about 1/4" in diameter. The holes are going to be blocked with a piece of acrylic about 3" up so the refugium can have a dsb. Water can get through but most critters can't. If I want even more crud strained out I could put filter floss in there whenever I'm making a mess in the tank. One of the reasons I'm moving the pump is because the water in that section gets stagnant.

Thanks all for the input,

Agu

[golfish]

You shouldn't have any problem with elbows on the intake. I had two 90 degree elbows coming off the sump into an Amp Master 3000 and there was no probelm at all with flow, except for one, too much flow through the sump. I had to re pipe it to a closed loop with three 90's and a 45 on the intake side and its still puts out too much flow for my 150 if I have the ball valve open all the way.......

[Cookoopod]

Agu,

Plumbing with a 1" prior to the pump will aid in reducing headloss. Size of fittings and type ( 90, 45, tees, etc...) both effect friction loss factors. If you plumb with the 1" returns (instead of 3/4") , velocity out of the returns will be reduced.

[Greg3333]

You may lose velocity in feet per second, but you will gain in gallons per hour.

[hcs3]

agu

careful with the 1" vinyl tubing. it has a tendancy to kink itself. it does not make bends well at all. also, if the hose is on the inlet side and the length is slightly long, the pump can cause it to collapse on itself and burn out the pump. keep the use of the tubing to short distances, like 4" or less. try to use pvc for as much as possible.

had any good wines lately?

henry

[Agu]

Thanks for the input. The 1" elbow did the job as there's no noticable reduction in flow. The refugium is sure a lot bigger now :).

Henry, No bends,just one straight connector with 1" vinyl, Thanks for the hint about it collapsing, I hadn't thought of that. There's only about 1/2" between hose barbs to prevent that from happening. Opened a '95 Hess Select cab after the job was done. Wish I had laid down a whole case!

Agu

[Cookoopod]

Job well done, Agu. Have any pics yet? I'd love to see your setup.