The staff are extremely friendly (that includes the four legged members) and they explain everything very well. We came to snorkel. The snorkeling gear worked fine and it was easy to avoid accidentally getting water down the tube. When we visited Devil’s Den, the water felt too cold to us even though it’s advertised as 72 degrees year round. It might be best to go during the hot summer to cool off or else you’ll be envious of the scuba diver’s wetsuits.
There were several scuba diver groups when we went. From what we observed this looks like a great place to try out scuba diving for the first time to get the hang of it if the open ocean is too intimidating. The spring goes down pretty deep and there was plenty of room to accommodate approximately 20-30 scuba divers and roughly 5 snorkels.
Our snorkeling reservation gave us 90 minutes in the spring. For us this was too long. We were pretty cold by the end and could have done just a half hour tops.
As far as if there is a lot to see in the den, there really isn’t. There are fish and at least one large turtle in the spring, but it’s pretty dark and hard to see much of anything. A pro tip is to hover by a scuba diver that has a flashlight to see a bit more, but it’s really just rock.
It came out to just shy of $80 for two to snorkel and rent snorkeling gear. I would consider bringing your own snorkeling gear to lower the cost, but I still think the price is a extremely high. I can see why some people call this a tourist trap.