Concrete or fyberglass pool? which is better

which is better
Answers:    If the mineral content in your local sea is a concern, stay away from the fiberglass - you'll be disappointed in the instrument it looks within a couple of years.
Calcium, lime, iron - adjectives of them can cause gruesome stains on the fiberglass. They're easier to keep at fjord on cement.
A pool is a man-made ecosystem that you are creating, and the goal is that "nothing" will grow, including mineral deposits.
Most of the chemicals you'll enjoy to add are to preserve algae & mold at bay. If you own to fight near the very hose itself, you'll be adding even more chemicals that you may not want to swim contained by!
I would say fiberglass.. its standard lamp weight and straightforward to use, far less messy...