Hi, my first post. Sweet.

I have the same unit and had a hard time using it. I had to install a plastic check valve on both ends of the tubing in order for it to work properly. The siphon would drop by the pump motor and lose its prime. Maybe you have this problem as well? I own 2 units with 2 extensions so 14 pumps in total and they all do the same thing. Crappy unit. never will I ever recommend this pump to anyone.

Once you manually pump the solution through all the tubing, set the programming. The way it works is that you select how many ML's you want it to dose and then choose how many times it should dose over a 24 hour period. It will choose the times for you, unless you choose only one dose per day. For pumps 2 - 11, it will then automatically dose 5 minutes afterwards. E.g., if you set your pump #1 to dose at 2pm, then pump #2 will automatically go off at 2:05pm and #3 at 2:10pm, etc...

Best of luck.