I ordered my Alkatronic from Coralvue since they received the second batch. Had some great support from Jonas and Erric. I want to share my lesson learns and hopefully can help someone with same issues.!
I throw PH probe cap with rubber band away. Didn't realize there is a rubber band inside the protection cap and it is used for something. First day basically I unboxed everything and thought the rubber band wasn't useful. Had to use ziptie and air line tubing to hold the probe afterward.
Pump C rattles like mad. Went through the manual, did calibration procedure. Pump C was working until the very first test. The inside tubing was wrong size and pump C pulled it off from plastic connector. Jonas helped me identified the issue and had Coralvue mailed me a right size tubing.
Inconsistent reading after replace Pump C tubing. Unit constantly retest. Black dots all the way for every test. Basically every 1 test was about 0.4 DKh higher than what it should be. The second and third test will match up fairly close. Air bubble accumulation was found between dosing tip to Pump C outlet connector. Reconnected Pump C tubine and applied silicone grease solved the issue.