Campervan, nice hotel choice, shame they don't have a pool. In the past we have used Bahar hotel pool although it was a year or 2 ago.
I know the Harman hotel allows people in to use pool as long as you buy drink/food, although this is about a 10 minute walk from Delta hotel.
I'm sure there are more hotels that will also let you use the pool if you purchase food or drink
Pat