Dosing line draining back into container

[Kiiyo]

I got this kamoer f1 dosing pump set up and it works, however it slowly drains back into dosing container.

Does it appear that I have anything set up incorrectly? I have a 1/4" line from the dosing container to the bulkhead on the container. This leads to a check valve and then a reducer barb fitting from 1/4" to (I think) 3/16" that leads to the dosing pump. All of this is fastened down with zip ties.

I recently added the check valve to see if it would fix the issue, but it was still happening before I added that as well.

I've primed the pump and it just slowly leaks from the inlet side back into the container. The outlet side appears air tight.

 

[Kiiyo]

I'm thinking about trying to get a replacement head for the pump since that was a bit finicky to get working initially. I had to massage the tube before it would even pull liquid.

Could this solve the issue?

 

[pooootiqe]

Try watching the meniscus when the pump is active - does it move forward continuously but suddenly retrieve backwards? If so the peristaltic pump head is likely bad (roller doesn’t fully seal off the tubing).

If not probably just a air leak somewhere.

 

[Kiiyo]

Try watching the meniscus when the pump is active - does it move forward continuously but suddenly retrieve backwards? If so the peristaltic pump head is likely bad (roller doesn’t fully seal off the tubing).

If not probably just a air leak somewhere.

The cover is black so I can't see what's happening in the head. But this is the issue I'm seeing. After it doses, the line looks fine. But a few minutes later and I see a large air pocket.

Safe to assume air is getting in somewhere?

 

[pooootiqe]

Yeah looks like one of the dosing tubing - pump tubing connectors is loose. Another cause could be the pump tubing is cracked but i highly doubt BPT tubings crack that easily (and you’d probably see liquid spewing out of the pump head lol)

 

[Kiiyo]

So I should look to replace the connector piece coming off the dosing pump itself?

 

[pooootiqe]

I’d try smaller ID silicone dosing tubing first.

 

[pooootiqe]

For a quick check - wrap some tape (teflon if you have it) around the 1/4 end of your reducer before putting on the tubing, and see if it still drains.

 

[Kiiyo]

I’d try smaller ID silicone dosing tubing first.

Are you referring to the tubing coming from the dosing pump? That tubing is what came in the box with the pump.

 

[Kiiyo]

For a quick check - wrap some tape (teflon if you have it) around the 1/4 end of your reducer before putting on the tubing, and see if it still drains.

I'll try this out and see if it makes a difference. This is my first dosing pump and I really wasn't expecting it to be this difficult haha

 

[pooootiqe]

Are you referring to the tubing coming from the dosing pump? That tubing is what came in the box with the pump.

The clear tubing yes, not the yellow-ish one. Would be weird if the stock tubing isn’t working.

 

[theMeat]

Is your dosing tube outlet above the waterline?
If not maybe creating a siphon

 

[Kiiyo]

Is your dosing tube outlet above the waterline?
If not maybe creating a siphon

Yeah it's above the waterline.

 

[Kiiyo]

Just to give an update to this, I've been talking to Coralvue and we've come to the conclusion it must be the tubing in the head of the doser where the issue lies. While they cover the head under warranty, they're saying that the tubing in the head isn't covered under warranty.

I'm currently trying to get them to send me replacement tubing for free. While yeah it's only like 8$ so I could just buy it, it doesn't make sense to me that they're even trying to get me to pay more to fix a product that was defective out the box. We'll see what happens, to be continued...

 

[JTP424]

Did you try it without the check valve? I know that seems counter intuitive. just seems like a weird add on personally, I understand the concept, just may be causing more trouble than it's worth with a liquid.
Additionally did you try it without the additional tubing at all? if you put your finger on the part that is the "in" side, does it pull a slight vacuum?

 

[Kiiyo]

Did you try it without the check valve? I know that seems counter intuitive. just seems like a weird add on personally, I understand the concept, just may be causing more trouble than it's worth with a liquid.
Additionally did you try it without the additional tubing at all? if you put your finger on the part that is the "in" side, does it pull a slight vacuum?

I removed everything else so it was just the tubing the pump came with directly into the dosing container, same thing still happened. The liquid would slowly drain back into the dosing container.

Just for the hell of it, I set up my desired dosing schedule and collected what was being dosed just to see if the air in the tubing didn't cause an issue, but the amount that got dosed was like 25% off.

 

[JTP424]

I removed everything else so it was just the tubing the pump came with directly into the dosing container, same thing still happened. The liquid would slowly drain back into the dosing container.

Just for the hell of it, I set up my desired dosing schedule and collected what was being dosed just to see if the air in the tubing didn't cause an issue, but the amount that got dosed was like 25% off.

Ah fair enough. Good scientific approach :)

 

[Kiiyo]

Ah fair enough. Good scientific approach :)

Thanks for the suggestion.