Crystal Pool (PVT) Ltd. Sangabo Mawatha, Anuradhapura 0716552500 crystalpool.lk Sand filters are cleaned by backwashing, which involves reversing the h2o move throughout the filter, and flushing the soiled water into a waste line. To accomplish this, They might should make use of a backhoe and also other heavy machinery. https://netwebdirectory.com/listings12792439/swimming-pool-construction-can-be-fun-for-anyone