Have you booked a package? If so the TO is responsible for your health and safety and should ensure that the pool is kept clean.

Hi Glynis

No its not a package, bokked flights through easyjet and booked the accomodation through travel republic and some extra days through on the beach

if when you get there you feel the water doesn't look right, cloudy etc, (you should be able to see to the bottom of the pool, the water should be crystal clear). Algae forms very quickly if not treated with the correct chemicals & soon ends up green. I suggest you look at the water for any signs & relay it back to reception & ask or demand they test the water balance, it is more than their reputation is worth if they don't keep the water quality correct & let you swim in it as it can make people ill.