Dosing Pump Question

[chase]

I've been testing the consistency of my dosing pumps over the past couple weeks before actually using them. I noticed right away that pump 2 was not dosing as much and after checking found air in the tubing. I'm not sure why it's happening but an air bubble seems to form below the intake to pump 2 between the airline/dosing pump tube connector. I made sure both ends are well sealed and there doesn't seem to be any back siphoning or anything going on. Pump 1 does not have the same issue and has been working fine. Has anyone else seen this? I've attached a picture so you can see what I'm talking about as well.

Thanks in advance!

[rimai]

It does look like you are not getting enough suction, but if you say that the ends are sealed, then it is not that.
Did you inspect the silicone tubing?

[chase]

Yeah, the tubing seems fine. When I mask it on with the client I don't see any lack of flow areas, it just seems like if i go more than 3 hours without activating it that bubble thing shows up. I took off the white part and just made sure everything looked okay. When I pressed it back down I noticed it clicked and I don't know if that had something to do with it, because when I spun the white thing around to get the tubes in the right directions the first time I don't remember if I pressed it down or not. I'll run it again today and see how it goes. Thanks for the help!