Dosing Pump Problem

[cadugauch]

I just setup my dosers and i am having a problem. I got the aquahouse dosing pumps...one for alk and one for calcium. Problem im having is after filling both tubes to the limit to leave it ready for dosing...the tube going to the sump sucks the liquid back (back siphons slowly) to the container. My pumps are positioned lower than the tube going to the sump...does this matter?

 

[ANFPO]

"My pumps are positioned lower than the tube going to the sump...does this matter?"

Technically it shouldnt because since its a peristltic pump, the rollers pressing on the tube only allow the water to flow when the rollers are spinning.

In real life, though, I would suggest:
1. NOT submersing the outflow tubing of the pumps in your sump's water, they need to "drip" into your sump.
2. make sure all your cennections are airliquid tight. Should be two connections only per pump.
3. raise the pumps above your sump water level as you guessed. Sometimes the rollers dont create enough pressure to stop the saltwater from backflowing into your chemical bottle. When you take the output from isde your sump's water, this should resolve as well.

 

[cadugauch]

Output is not under water...so liquid is sucked back and also air...not saltwater

 

[Rbs07fxstc]

I would try placing pump higher than sump then.

 

[cadugauch]

Problem appears to be solved after hanging the pumps higher than my sump

 

[nivram]

The rollers aren't pinching the tube enough. Did you buy them new?

 

[cadugauch]

Yep brand new...problem is still happening...im going to open up the pump later today

 

[cadugauch]

I just cant understand how both pumps brand new have the same problem!

 

[BrassMonkey]

wrong tubing size/wall thickness?

 

[cadugauch]

wrong tubing size/wall thickness?

using the tube that came with the pump!

 

[BrassMonkey]

lol, well either the tubing or pumps are out of tolerance and is not pinching the tube all the way. i use the tygon pharmed so i never have to remember to change the tube out, its stiff tho, not sure those pumps would like it. throw some good quality silicone in there and see what happens.

 

[ANFPO]

Agree with above. Probably the factory tubing is too small in outside diameter or the rollers are too narrow.

You can increase the outside diameter of the tubing by adding tape to it. SpectraPure does something similar but i forget which material they use.

 

[nivram]

Contact CoralVue. They have a forum here on RC.

Some how air is getting into the tubes. Can you post pics of the connections? Maybe you don't have the airlines connected to the tubing well?