Hi! We purchased our house 3 years ago and never have had any issues with our pool until this year. We have a an in ground vinyl pool approximately 18k gallons with a hi-rate sand filter. We brought a sample of water to the local pool store and they tested for 10 different things all were perfectly in balance. They suggested we try a high concentrate algae remover because it had a little green look to it. That did remove the green but still very cloudy. Tried a clarifier and hocking it with no luck. I read the sand could need to be changed or something could be broke in the filter just not sure we know enough to try taking the filter apart. Before we attempt has anyone else had a similar problem or have any advice?