I have an above-ground pool 12′ x 24′ and filled it with well water from an artesian well. The water was crystal clear for days when I decided to add some chlorine pucks. The water turned green. It is still transparent, but green. I have a floating pool duck that these chlorine pucks go into. After about an hour, the water turned green. I have used these chlorine pucks in the duck for years and no adverse effects…until now. So how do I go about getting rid of the green in the water? I have a sand filter pump on the pool and the pool holds approximately 7000 gallons.
One of two things happened when you added the chlorine to the pool water – either the iron in the water came out of solution (usually due to a higher pH, or the ph change caused the discoloration). Chlorine tablets have a pH of 2, so they tend to lower the pH of the water. Both low and pH can cause green water, low is usually a dull metallic looking green, high pH is fluorescent green. Iron causing green water is somewhere in between. With the sand filter, our FerriTabs sold on our website would work. One tablet per 3,000 gallons to remove iron, and you can add a tablet when you have to add water with the hose throughout the summer. Best of luck to you!