Welcome to TFP!

Foam on the water is sometimes related to using a product with additives not ideal for pools such as scented or splashless bleach. It would help if you posted a full set of water test results and confirmed which test kit you use to test your water. Here at TFP we're all about accurate test numbers, and the TF-100 or Taylor K-2006C test kits have proven themselves great for the task.
Also tell us how you typically chlorinate the water and any other products you may add on a regular basis. If you suspect you have algae after opening, be sure to read our
SLAM Process.
Our
Pool Care Basics page has lots of great info, so be sure to check that out as well. Enjoy the forum.