Dosing Pump Question

[sledge75]

I was wondering if a dosing pump would allow me to top-off from a reservoir with a higher water level than my sump without allowing it to drain due to syphon action.

A little further explanation. I have a top-off container that sits in a space beside my stand thats 24 inches high. I use it to top-off into the sump which is a standard 10 gallon. With the current pump I'm using I can only fill the reservoir half way or when the pump shuts off water would continue to syphon until the water levels are even. I was hoping that a dosing pump would pinch the hose and prevent the continued syphon action but I'm not sure exactly how one would work. I was thinking of this one:
Aquamedic Dosing Pump

 

[Reef55]

Yes. it would pinch the tube. Why not put your pump above the reservoir?

 

[Mr. Slippery]

I think those pumps are made to be placed above the resevoir, and can draw from up to 3 feet. I have to do the same thing to run a kalk reactor and am also worried about the siphon. I was under the impression that these pumps only will pinch the siphon off if it happens to stop just in the right place, but it won't always happen that way.

 

[Corwyn]

Someone had a link to a pump at marine depot ( I think, 'cause I can't find it again)
for around $13 that would do this really well.

C

 

[sledge75]

I would have tried putting the pump above the reservoir but its an in sump only type pump and there is no inlet, so I can't attach a hose to run down into the reservoir.

I have to get a new pump or figure out another way, so I was hoping a dosing pump would solve my problems. Plus I would prefer to have the pump above the reservoir rather than in it for logistical purposes.

 

[Chris A.]

You could always put a check valve on the pump.Just an idea

 

[JohnK]

Another solution would be simply to run the line coming from the dosing pump (or current top off pump for that matter) to the top of the display. I assume that your using a water level sensor of some sort to control the top off, and the sensor is located in the sump. If so it dosen't matter where the top off water enters the system.

I do it this way for the kalk dosing on one of my tanks. It uses a dosing pump but I don't trust it to prevent a siphon everytime. I also don't trust check valves. I just zip tied the line from the dosing pump to one of the slits on an overflow box, with the end sitting an inch or so above the water line. No way to siphon in either direction.

 

[agent6473]

Corwyn, I believe you're thinking of the aqualifter pump.

 

[shawn]

A peristaltic pump would probably work good for you - they don't allow flow in either direction when they are not pumping, and are generally designed for controlled, relatively low flow rates such as are good for dosing or top-off. Check ebay for "peristalic" or "enteral feeding" pumps.