My pool has been surrounded by clay paver's laid on a sand bed for the last 20 years and still looked like new after I gave them a pressure wash.
Usually saltwater.
No
It could be fatal.
You would be best of taking a sample to a pool shop for testing and getting their advice on the remedy.
Mostly underwater brine pools and saltwater springs.
Hydrochloric acid and potasium help alot
Salt water pools
Saltwater makes up a majority of the oceans. It is a habitat for sea life of all sorts. It is also now used in personal pools.
All pools need something to help keep it clean and safe. Chlorine has long been the sanitizer of choice. Saltwater is no different, as the charged cell breaks down Salt in the water into Chlorine.
Obviously the pool floor is not smooth.
They are one and the same. THEY BOTH ARE CHLORINE POOLS!!!
You have a penny in both types of pools ... ???