That depends on the thickness of the layer of sand required.
Looking at the chart shown here:
http://www.backyardcitypools.com/AG-Pool-Sand-Volume-Chart.htm
You'll need 3 yards of masonry sand.
I have a 15 foot round pool that is 4 feet high, and it took about 12 hours to fill it up all the way using one hose.
How much sand for a 16' x 31' pool with a armer sheild and cove
2 tons
6 tons
assuming you have a pentair 2.3 21" 51-1/2" 50 24,000 225 lbs.20 grit silica sand If on the other hand you mean the amout of sand needed to cover the floor of a 21' round pool to a depth of 2", the answer is 3 to 4 tons.
I used a sand base for our 20' round above ground pool. It's much easier to deal with after the pool is gone. Greener too.
Simply ask the company who would be delivering your sand for the sized pool. They usually know the average cubic tons per size pool. Should be 4 tons.
The amount of sand in a pool filtration system depends on its size.
I'm having trouble visualising a 16 x 4 pool as being round. It sounds rectangular to me. Something round can only have one dimension, the diameter, and the height which you give as 2 inches. Please resubmit.
You don't use sand to level the ground that the pool sits on. The sand is used on the inside of the pool, after the ground has been leveled by taking the highest point down to the lowest point after the grass has been removed. The manufacturer's usually recommend 2" of sand on the inside of the pool before the liner is installed. It sounds like you are installing a used pool, since you do not have instructions. Here is a link to some instructions that could possibly be used. http://www.royalswimmingpools.com/install.htm
Had the same problem. Turned out that i needed the electrodes replaced, since doing that, its working fine, now i have a problem with 2much sand in the filter (No idea how much sand is needed)
Do not put sand in your pump. If the sand your are referring to is in your pool filter then it should be changed every 4 to 5 years.
140# of sand is required.
Never put sand on the bottom of a pool....if you are curious, do a little web search for Sharon Stone and her experience in wanting sand in her pool to feel like the sands of a place she visited....needless to say, the pool's filter immediately stopped working, all water had to be removed, new pool filter installed, and water refilled.
For what? Building a cove for a vinyl liner. Adding sand to a sand filter. Building a sand box. For the base of a pool. ????
Your filter will tell you on the side of it how much media sand to put in it.