In order to really enjoy swimming and sunbathing while in Sarandë, it is really necessary to spend at least a day in Ksamil. There are a few beaches from which it is even possible to swim to one of the nearby islands. Paddleboats are available for rent, or else you can pay a boat to take you to one of the islands which are a little further away.
There are nearby restaurants which have freshly caught fish, and mussels from lake Butrint. You can get to Ksamil by following the road towards Butrint.