You just changed the sand in your sand filter and, after running the pump for a short time, you notice that there is sand at the bottom of the pool. This guide enumerates some of the possible causes for this sand and discusses ways of avoiding or reducing the sand collecting at the bottom of your pool.
1. LONGER RINSE CYCLE - When you change your sand, you should BACKWASH it to eliminate the fine sand that exits in most new sand and tends to cycle through the filter and end up at the bottom of your pool. Than you will want to set the filter to "RINSE" to pack the new sand down and reduce loose sand. Remember to turn off the pump before switching valve setting so that you don't damage the valve's spider gasket.
2. TOO MUCH SAND IN TANK - If you have too much sand in your filter tank, your backwash and rinse cycles will not be as effective. Leave at least 6" of space between the top of the sand and the top of the filter tank.
3. BROKEN LATERALS - If any of the laterals at the bottom of your filter are broken or cracked, they will allow sand to feed back into your pool.
4. FAULTY VALVE GASKET - A faulty multiport spider gasket will allow debris and loose sand to leak into the return post during the "WASTE" or "RINSE" settings. Make sure you turn the pump off before changing the valve setting, or you will damage the spider gasket.
5. MINIMAL EQUIPMENT - Some of the less expensive sand filters, like many used on above ground pools, do not isolate the sand well during filtering and this allows sand to pass into the pool.
6. WRONG SAND - You must use only high rate No. 20 Silica Sand to fill your filter tank. Other regular sand, like kids play sand will have debris in it and will not pack and unpack like pool sand.
If you have any other questions about pool and spa products please do let us know - we are here to help!