Our pool has turned green and we do not have winter cover on yet, but it is drained down a little for winter. Will it hurt if we leave cover off and just drain and refill pool in spring or will it leave algae stains? It is an painted inground pool.
it is likely to leave significant discoloration from the algae already present and knowing that it will continue to grow over the course of the winter, particularly during warm periods. The extent of the discoloration depends on a number of factors, but just know that your clean up efforts in the spring would be significantly more difficult that cleaning it up now when algae is fresh and minimal.