To put the numbers into the proper context, Tapley explained just how much water is used in backwashing filters each year. “A typical backwash for a sand filter is 200 to 250 gallons and it’s recommended to backwash them once a week,” explained Tapley, “that’s over 5,000 gallons a year of freshwater that you have to put back in the pool to replace it. Keep in mind that the skimmer starts grabbing air because the water level drops. So you got to double that. I mean, you’re really talking about 10,000 gallons per pool.”
“When you’re cleaning the filter and you dump a couple of hundred gallons of water out of the ground, you lose that pretreated water,” explained Tapley, “and when you’re putting the fresh water back in, then you got to go right back to your test kit and start readjusting the pool. The service guys realize that every time that they have to put more chlorine in because they just top the pool back up and give it a couple of hundred gallons of water. So that said, I feel like when we have pretreated water that we’re capturing and putting it right back in, that is a savings right there itself. If it is a saltwater pool, of course, then we’re saving the salt water.”
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