Are you sure your cya is low? You can be using up the bleach because you are starting on algae from all the rain. You should not lose any chlorine even with low cya if there is no sun So I would take the chlorine up to shock - you will need to know your cya level to get it to proper levels as per the chart

Use the info in this chart to help you figure out what levels of chlorine you need to maintain in your pool based on the amount of CYA (cyanuric acid, also called stabilizer) that you have in your pool. (FC = free chlorine)

Stabilizer . . . . . . Min. FC . . . . Max FC . . . 'Shock' FC
=> 0 ppm . . . . . . . 1 ppm . . . . . 3 ppm . . . . 10 ppm
=> 10 - 20 ppm . . . . 2 ppm . . . . . 5 ppm . . . . 12 ppm
=> 30 - 50 ppm . . . . 3 ppm . . . . . 6 ppm . . . . 15 ppm
=> 60 - 90 ppm . . . . 5 ppm . . . . . 10 ppm . . .. 20 ppm
=> 100 - 200 ppm . . . 8 ppm . . . . . 15 ppm . . .. 25 ppm

Last year in PA in june we got flooded, and my pool turned green from all the run off and new water. I shocked it and kept it at shock till the levels held overnight. Good luck, and wishing you good weather