New Chihiros dosing pump air in line

[Arjunb]

I just got a new chihiros 4 head dosing pump. I primed it dosed using it all fine but gradually after dosing its losing prime. Fert level from the tank outlet side for all tubes going down.
From the inlet end its even more strange. Its just not going down uniformly but as pockets of air. The seals are snug tight as its brand new 2mm/4mm tube. I have seen lot of other posts complaining of this, and will affect dosing quantity. What is the solution?

 

[Administrator]

Air in tube means you didn't insert or calibrate well.
You can cut a section of tube and reinsert, recalibrate.

 

[Arjunb]

I had calibrated well and primed it several times. The problem is i was using silicone tubing. Like its well known in planted tank community silicone is permeable to gas. What i noticed is a small air bubble formed in the pipe and that kept expanding and making big pockets of air. The silicone is not leaking but its the nature of the material. Hence i swapped it out with PVC pipes and no more bubbles or air pockets. BTW the pockets of air was reducing dose by 0.5 to 1 ml. I did not buy the tube from chihiros so cant comment what they are made of, but i got 2mm ID / 5 mm OD tube that had pretty thick walls, still over 24hrs air seeps in.

So not a defect with the heads or how its installed its the tube material causing this. Hope it helps!!

 

[Administrator]

Ok, recommend using our original tube 2/4mm.