Multiacuatic

Multiacuatic has been recommended to us as the best dolphin and whale watching tour at Gran Canaria. It was an unforgettable experience.
The boat sets every day onto the open sea in a search for wild dolphins, whales and sometimes sea turtles in their natural habitat. These guys have been doing this for years, and they have a very high success rate of finding the dolphins almost every time.
Your ticket guarantees you entry as many times as it takes for you to see dolphins — so if you are unlucky on your first visit, you get to come for free as many times as it takes to see them.
Thus it might be good to book this earlier than on your last day of your trip, just in case. But our (unrelated to multiacuatic) tour guide who has been living at the island for years mentioned that this happens rarely, as the success rate is extremely high.
The ride costs 30 euros (soft drink on a boat included) and it has been definitely worth it. Seeing the numerous pods of dolphins feeding together with hundreds of birds and then having them follow your boat is just a unique experience — so much better than any staged theme park.
Our guide at the boat was an extremely merry character who gave us some information about the wildlife we were about to see in three languages. He kept everyone entertained with his joking, yet gracefully handled the unlucky people who turned out to be less tolerant to the open sea. If you think that it might be you, beware: this is a decent sized (two floor) boat, but still, it’s not big enough to prevent a certain amount of rocking natural to the open sea. Also, it gets chilly on the open sea — they do provide some blankets, but it’s worth grabbing your own jacket even on a very hot day.