pump suggestion

[wmboots]

I know I posted this somewhere before but don't remember where.
The little giant pump I'm using on the closed loop system on my 150 is so loud and is producing so much heat I have to leave all three doors open on my stand.
I'm open to suggestions for a replacement pump, I have as 9.5 mag but I'm not sure it will create enough flow.

 

[realfish]

How much flow are you looking for. I have a Reeflo Tarpon that I only used for probably a month. It wasn't enough for my 200 display/basement sump. It's really quiet and low wattage and it is fan cooled so between the low watts and the fan cool it puts off very little heat. It does 1440 gph and 23' of head.

Let me know if you are interested.

 

[wmboots]

Do you know the gph at 6' of lift? The initial gph you listed is better than the little giant. If the lift is still in the 1200 gph please pm with what you want out of it

 

[realfish]

Sent you a pm. It been a long time since I owned a little giant pump, so take this for what it is worth, but they were anything but quiet.

 

[grouper therapy]

If it is an actual closed loop then the 6' of lift is irrelevant. There is no vertical head on a closed loop.

 

[jef4y]

grouper therapy;762020 wrote: If it is an actual closed loop then the 6' of lift is irrelevant. There is no vertical head on a closed loop.

Explain please...

If there were 50', I don't think the pump would possibly operate. How is there a difference whether it's a closed loop or simply a return pump? What am I missing?

 

[realfish]

My guess is with a sump, you are only working against gravity. With a closed loop, gravity is working for you and against you. That being said, I doubt that it is a 1:1 relationship. Also, I would think depending on the complexity of the closed loop system you would have a good number of fittings creating lots of friction loss.

 

[grouper therapy]

JeF4y;762233 wrote: Explain please...

If there were 50', I don't think the pump would possibly operate. How is there a difference whether it's a closed loop or simply a return pump? What am I missing?

RealFish;762240 wrote: My guess is with a sump, you are only working against gravity. With a closed loop, gravity is working for you and against you. That being said, I doubt that it is a 1:1 relationship. Also, I would think depending on the complexity of the closed loop system you would have a good number of fittings creating lots of friction loss.

A closed loop pulls water from the same source it pumps water to. Any vertical lift loss is negated by the vertical fall gain. It is exactly 1:1 in regards vertical head loss but Realfish is correct that the friction loss can have an impact on both closed and open loop systems. If the pipe is properly sized then that friction loss can be minimized to a point that it almost becomes irrelevant in the systems that we run. There are of course exceptions to the last statement. To answer your ? of 50 feet scenario yes if the friction loss did not exceed the pump's max .

 

[realfish]

Here is a nice technical article if anyone cares

 

[kilo32]

Here's a head loss calculator that might help.

 

[jef4y]

Interesting. I hadn't considered the gain in the "falling" water feeding the pump offsetting the head loss.