I just opened my pool the first time, pool was installed last Oct. I also have a mesh cover. Water was 56 deg., clear with dirt/silt stuck to sides and bottom. There was a pile of leaves,straw,(I just planted grass), mesh cover instructions, dead worms, and dirt. Used Leaf rake to pull out the pile, smelled like stagnant water and garbage. Brushed sides and bottom, vacuumed, water was somewhat brown and cloudy, ran filter about 8 hrs. This morning water was clear with a little silt on bottom in spots. All chems up to specs. One more light vacuum and iam good to go.