I recently setup my Coral Box WiFi doser. No matter what i do it does not hold siphon and I get air bubbles in the tubing. I bought the bundle so im using that container. I have tried both the check valves that come with the pump and upgraded ones i bought with the doser. I am using the tubing also purchased with the pump. I even tried switching pump heads. I have the same exact dosing setup on another tank and its been running for a year now with no problems. I am just hoping maybe someone might have an idea why I am having this trouble