I use the Intex pool startup kit. It has sanitizer, pool test strips and shock. Add Sanitize which is granular chlorine. If you have a pool brush, brush pool. I actually use a mop. If its really dirty you may have to get inside pool to mop, in which case add Sanitize after. Then run filter for 20 minutes and use test strip to check pH & alkilinity. If not right pH add another dose (booklet in kit says how much per 500 gals of water)and run filter another 20 min. Then add Shock and run filter 4-8hrs. If you don't have a filter, then you probably have to drain, clean with regular liquid bleach & mop then refill.
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