We have had a Hayward for 33 yrs.--we also changed to Zeobrite (instead of sand) It is wonderful.
Sand
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A filter paper. ;)
how do you clean jacuzzi sand filter, and replace sand
distinguish between slow and rapid sand filter
Nothing if its a sand filter However if sand is coming into the pool from the filter then you may have to replace one ore more laterals in the sand filter as they have worn and are letting sand through to the pool,
The best sand filter I have seen up to now is one that I scored along with a new magnapool chlorination system last year. I have never seen the water kept as clean as it is now. The trick is not so much in the filter as in the filter media. Instead of sand this unit has a material called diamond cleenhttp://www.poolrite.com.au/new-products.htm
Do you mean how do you install a sand filter?.
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differentiate between slow and rapid sand filters
If you have a sand filter the laterals in it may be starting to show signs of wear these wil blow sand from the sand filter into the pool when they wear out.
Your filter will tell you on the side of it how much media sand to put in it.