No absolutely not unless you want to waste a lot of water you backwash a pool when the pressure in front of the filter becomes too high or goes into the red.
first of all there shouldn't be a lot of sand at the bottom of your pool. assuming you don't live on the ocean where sand could become air born the only thing that makes sense to me is that something went wrong when you backwashed your filter. to get rid of the sand vacuum the pool every day until it disappears
If you take a sample to a pool shop it takes less than a minute.
Twice a day.
its better to to do twice a day for example taking a bath it should be before going to work and before sleep in the evening
Twicw a dah
Twice a day
Twice a day
twice a day every day
Once or twice a day
Twice a day.
twice a day!
Someone deficated in the pool. Or cleaned the skidmark residue.