Temperature and swimming in early April in High Atlas area

We are going to Morocco over Easter this year, a couple of nights in Marrakech, a trip to the desert and then three nights in the High Atlas area (possibly Ourigane). Holidays mean swimming for our children, does anyone know whether it is usually warm enough to swim in an unheated outdoor pool at this time of year? It does affect my hotel choice as at the moment I'm considering La Roseraie as it has a heated swimming pool and is cheaper than some of the other hotels but does have mixed reviews.