Zuma Tours took us from Jaco to Santa Teresa and from Montezuma to Alajuela. The ride was great in both directions (though the boat was rather late leaving Jaco), and the staff was very accommodating.
Scuba diving at Isla Tortuga was a lot of fun. We went on a Sunday morning and were the only two people on the Scuba tour (we shared our boat to and from Isla Tortuga with some snorkellers, all of whom said they enjoyed their time). Our Scuba guide/instructor, like the rest of the Zuma Tours staff, was professional, experienced, and multilingual. We had a fantastic time under the water - the water was warm, mostly clear (except in tight spaces where the current picked up), and our guide made pointed out a lot of aquatic wildlife that we wouldn't have noticed otherwise.
Isla Tortuga is pretty touristy, and not our normal thing, but we still had a fantastic time. This was our second trip using Zuma Tours, and I'd recommend them highly. The equipment and vehicles are all well-maintained, the staff is great, and (except for one late start) they've always gotten us where we want to go in good order.
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