Playa Puerto Morelos is a beach on the Caribbean coast of Yucatan Peninsula in Mexico. This is a great beach! The only problem are algae (since 2010) coming from the Atlantic ocean - more in summer, less in winter. So you'll have to choose expensive beachfront resorts, because these have the best cleanup procedures against algae. All other beach areas are completely depressive. Shore and seabed: sand. 
In Puerto Morelos, rooms' fares range from US$50 to US$200 per night. At the moment, most of properties are overpriced. They should either make their price tag lower, or begin to remove algae more carefully.
The best time for a holiday on the beaches of Yucatan Peninsula is a dry season from November to April. However, the summer half of the year is also good enough, since there are no crowds of tourists, and the sea water is warmer.