Water Stained Table

I bought a beautiful love edge cypress table off a local buy/sell/trade page for $160. I believe the top is coated in epoxy resin. The issue is it was left outside on a back patio where is is scratched and dull and cloudy with hard water stains. Trying to determine the best way to polish it up. My thought is to sand it with 400 up to 3000 and then polish it with some polishing compound? Does anyone have some experience or better suggestions? Wish I could upload some pictures…