VEVOR 13 in Sand Filter Pump for Above Ground Pool, 0.75 HP 3500 GPH, Swimming Pool Sand Filter Pump with Pre-Assembled Core & Leak-Resistant Design, 6-Way Valve, High-Efficiency Filtration for Pools

The maximum capacity of the swimming pool is around 5,000-7,000 gallons.

The product does not have a self-priming function. The product cannot be placed on the water surface for pumping.

A 13-inch pump/filter requires 20kg of 20-mesh silica sand or about 1.3kg of cotton balls. However, cotton balls come in various sizes, so just make sure not to exceed the maximum allowable amount.