throttling a pump with a valve?

chriss1992 · Mar 31, 2020

If you tone back a pond pump that you use as a return would that damage it overtime or cause it to blow the tube its connected to off eventually due to pressure
the valve
the pump

Ultra Aquatics · Mar 31, 2020

Nothing wrong with valving down a pump on the output side, you never want to limit the input though.

chriss1992 · Mar 31, 2020

James404 said:
Nothing wrong with valving down a pump on the output side, you never want to limit the input though.

yep using it on a return
thank you!

tamanning · Mar 31, 2020

Most pumps need to have 30% of their rated circulation to function without damage. the pressure will not build. the valve however will start to build up salt coraline algea and the like so you will need to watch it.

sarcophytonIndy · Mar 31, 2020

The internal DC return pumps are so cheap, quiet and reliable these days. Hard to beat, especially since you can adjust the power usage / flow with a controller.

chriss1992 · Mar 31, 2020

sarcophytonIndy said:
The internal DC return pumps are so cheap, quiet and reliable these days. Hard to beat, especially since you can adjust the power usage / flow with a controller.

thats probably where I'll go longterm just needed something more of a quick three/four week fix for now

wackyreefer · Mar 31, 2020

Sort of related question. As for external water pumps (magnetic drive pump) in say a water mixing station. If you have the pump on and close the output off with a ball valve once your tank is full for 30-60 seconds with the pump on before turning off the power to the pump, would that damage the pump?

sarcophytonIndy · Mar 31, 2020

wackyreefer said:
Sort of related question. As for external water pumps (magnetic drive pump) in say a water mixing station. If you have the pump on and close the output off with a ball valve once your tank is full for 30-60 seconds with the pump on before turning off the power to the pump, would that damage the pump?

Should be fine for a short time

X-37B · Mar 31, 2020

wackyreefer said:
Sort of related question. As for external water pumps (magnetic drive pump) in say a water mixing station. If you have the pump on and close the output off with a ball valve once your tank is full for 30-60 seconds with the pump on before turning off the power to the pump, would that damage the pump?

Not sure why you would want to do that but yea. Turn the pump off first.

wackyreefer · Mar 31, 2020

90's reefer said:
Not sure why you would want to do that but yea. Turn the pump off first.

I guess if pump and power to pump is in basement for instance. If you were able to shut the Valve closed then run to turn off power it would be more accurate. Versus turning off power too late or too early.

Boiler93 · Mar 31, 2020

90's reefer said:
Not sure why you would want to do that but yea. Turn the pump off first.

Because the pump is far away maybe?

X-37B · Mar 31, 2020

wackyreefer said:
I guess if pump and power to pump is in basement for instance. If you were able to shut the Valve closed then run to turn off power it would be more accurate. Versus turning off power too late or too early.

Then you need to be running a check valve.

wackyreefer · Mar 31, 2020

90's reefer said:
Then you need to be running a check valve.

Unsure how a check valve would address shutting off the pump too early or too late. I would think a check valve would address back syphon but that's a different problem. Please elaborate / educate us here

Hemmdog · Mar 31, 2020

wackyreefer said:
I guess if pump and power to pump is in basement for instance. If you were able to shut the Valve closed then run to turn off power it would be more accurate. Versus turning off power too late or too early.

Get a Kasa smart powerbar/outlet, you can turn it off with your phone from anywhere in the world.

X-37B · Mar 31, 2020

wackyreefer said:
Unsure how a check valve would address shutting off the pump too early or too late. I would think a check valve would address back syphon but that's a different problem. Please elaborate / educate us here

Sorry was replying to wackyreefer. Either way you always turn the pump off before completly closing a valve. Not even sure why you would do it anyway.
Its just common sense.

wackyreefer · Mar 31, 2020

Hemmdog said:
Get a Kasa smart powerbar/outlet, you can turn it off with your phone from anywhere in the world.

Wow great idea. Thanks!

Hemmdog · Mar 31, 2020

wackyreefer said:
Wow great idea. Thanks!

I love mine!

Albertan22 · Apr 1, 2020

wackyreefer said:
Sort of related question. As for external water pumps (magnetic drive pump) in say a water mixing station. If you have the pump on and close the output off with a ball valve once your tank is full for 30-60 seconds with the pump on before turning off the power to the pump, would that damage the pump?

90's reefer said:
Sorry was replying to wackyreefer. Either way you always turn the pump off before completly closing a valve. Not even sure why you would do it anyway.
Its just common sense.

He's talking about a mixing station pump. Most of us with mixing stations will have a valve on the end of the hose that we're using to refill the DT and the mixing station is across the room or even in a whole different room or floor of the house. You naturally stand next to your tank while you're pumping the new saltwater into it and not next to the pump. Once the tank is filled, you shut the valve and run to turn the pump off, or perhaps break out the phone and turn it off via some kind of wifi switch.

@wackyreefer I don't think it's great for the pump, but I do it anyway and try to be as quick as I can in shutting off the pump. I use a pretty cheap old second hand pump for my mixing station and don't give it a lot of love. We don't really need to be concerned with mixing station pumps being reliable like a return pump (failure won't risk massive damage to our DT) so I don't worry about abusing it that much.

wackyreefer · Apr 1, 2020

Albertan22 said:
He's talking about a mixing station pump. Most of us with mixing stations will have a valve on the end of the hose that we're using to refill the DT and the mixing station is across the room or even in a whole different room or floor of the house. You naturally stand next to your tank while you're pumping the new saltwater into it and not next to the pump. Once the tank is filled, you shut the valve and run to turn the pump off, or perhaps break out the phone and turn it off via some kind of wifi switch.

@wackyreefer I don't think it's great for the pump, but I do it anyway and try to be as quick as I can in shutting off the pump. I use a pretty cheap old second hand pump for my mixing station and don't give it a lot of love. We don't really need to be concerned with mixing station pumps being reliable like a return pump (failure won't risk massive damage to our DT) so I don't worry about abusing it that much.

This was the reply I was originally hoping for. Thanks for taking the time with the long detailed reply.

eggplantparrot · Apr 1, 2020

centrifugal pumps don't build up internal pressure so why would it get damaged?

if you slowly close the valve it would actually run with less resistance as it doesn't have to redirect water flow anymore, since the water stays within the impeller cage, rotating along with the impeller.

if you were to slam the valve closed with high speed flow then the sudden stop of the water movement could probably cause damage to the impeller so don't do that