TFP basics.
Don't do anything until you can test yourself.
Step 1, you need CYA to protect your FC. Test your CYA, add enough, after testing, to get to at least 30ppm. For normal operations in Ontario, 30-50 CYA is fine. Use "chlorine stabilizer" in a sock (old one, tied off, filled with stabilizer, and put it in the pool carrot on a stick style in front of a return).
Step 2, add enough liquid chlorine to maintain your FC for your CYA. If the sock is in the pool with enough CYA to raise to 30, consider your CYA to be 30. Link-->
FC/CYA Levels
Step 3, 4, 5...manage your pH next, then CH.
Why type of pool do you have? (vinyl, Fiberglass or plaster?)
Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.
www.troublefreepool.com