If by CH you mean Chlorine, you're probably not getting a reading because you have no stabilizer in your water, and the "goo" in the water and the sun are just eating up all your chlorine. Get a drop-based kit, run a set of test numbers for Cl, pH, TA, CA, and CYA, and post them here along with info on what type of finish your pool has and what exactly (ingredient names, not just "shock") your pool opening service added to your pool. Then we can get you headed in the direction of clear water.

Welcome to the forum!

Janet