I have a 24-foot above-ground swimming pool I had a huge algae problem at the beginning of the season and I have been putting lots of shock in it to get the algae to die I have used all different kinds of things in the pool like yellow gone and a non copper algaecide the pool is now stuck on bright green and it has been that way for a few days I have added lots of shock in the pool granulated and liquid and the pool is just stuck on bright green I have also removed my pucks that have the stabilizer in them. I also removed as much debris as I could feel while walking around in the pool. Last night I added 4 and a half gallons of liquid chlorine and 2 lbs of granular shock. This morning pool is still light green. No change in color from yesterday. Is it possible I need to change my sand even though its only almost 2 years old?