Below is cut and pasted from another post, re my Cancun trip in Dec, 2016. I believe that the Cancun & Isla Mujeres dives are mainly the same sites. Im not sure if the spotted eagle rays are still there in March. I was in a similar situation - went to Cancun bc of free housing. Im glad I went diving. Note: Ive never dove Cozumel, so dont have that standard of comparison
I just came back from Cancun in early Dec. I only did 2 dives there, but they were good.
I dove the C-55 wreck & the nearby reef as a 2nd dive. We had hoped to do the C-58 but the buoy was missing. The C-55 (and the C-58) is at 80' and the current can be strong - so its an advanced dive. We ended up going down the line, but it is often a drift dive. Lots of eagle rays & lots of fish. Not much of a wreck, the C-58 is supposed to be better, but lots of life.
The nearby reef - I believe its called "No Name Reef" -- but its the reef that is generally done as a 2nd dive, was the highlight of my vacation. A ~60', drift dive. This was a great reef, lots of life, a baby bull shark, eagle rays, swam with a green turtle for a bit, an eel, a big Nassau Grouper, just tons of fish, and a very healthy reef.
I would recommend diving one of these wrecks (the C-58 is prob better) and the nearby reef. Unfortunately I didn't dive any of the more OW sites, so I cant recommend anything else.
I dove with CancunScubaDiving.com, Alberto was a great DM. It was my first drift diving and he was great. I mainly chose them bc they were close (Km 3.5). I note that they may have been a bit pricier. They seem like a small outfit - they had a fairly small boat (backroll off the side, removable ladder on the side). There was only one other diver with me. I do note that they had us on a 30 min limit on the wreck dive, which maybe was a bit short.
