Nautilus is probably successful because the are located at the strip and the first center you will see if you walk there.
It was relatively cheap so I decided to give it a try. The result was a 3 hour in and out trip with two dives a 30-40 minutes on a small boat with 12 other people. The boat has no sun protection and it is so small that you have to put on your fins and everything else in the water.
I made more then 160 dives all over the world. But I never saw so bad equipment in the whole life. The vests were ragged and the tubes on the regulators cracked. I was really lucky that I had my own equipment.
There are better centers in Taganga.

Great communication. I set up my fun dive via email and Nautilus' response time and information was spot on. There's a great vibe at the dive center. Between dives we went to a tiny beach for . snack. one of he dive masters took banana skins and threw them up onto the steep overhanging cliff face. Initially I thought this a poor environmental decision until I saw them ... a half dozen giant iguanas clamoring over the cliff to munch on the gifts from below.

I went diving with Nautilus today and loved it! Great crew and it's nice to be with a family business. We saw lots of fish, beautiful coral, eels, stonefish, lobsters, and lots of stuff I don't know the name of. Inbetween the dives we had lots of snacks and a drink on the beach with everyone on the boat. All photos are included so we took a GoPro under water and they send all the photos to you by e-mail. Great dive school!

Had a great time completing our first open water dives! Price was great with a added extra of stopping in a hammock in the park! Darwin was amazing very patient, informative but with a relaxed approach, his english is amazing and we wish him the best! Thanks once again