We rented last summer at Le Torre and apartment was next to one of the lakes. We didn't have any mosquito problems but the patio was infested by tiny annoying fly type insects. They were all over the walls and the ceiling of the patio area, millions of them. No sooner did we get rid of them when they would start to reappear again.
The keyholder reported the problem to PW but certainly nothing was done during the 2 weeks we were there, so I suspect it's just a fact of life when living near water in Spain.