You can do Colombia at 70-80 feet, in the first place, and, as with any more or less abyssal wall dive, you just need to exercise decent buoyancy control. If you are relatively new, make a point of discussing that with the divemaster BEFORE you get to the dive site (when he will be preoccupied with dive briefings and getting the herd geared up). If you dive with a buddy who is a friend, pick one who has more experience than you do just to give you more confidence, and be sure to tell him/her of your experience level and any concerns you have. Your certification dives should have taken you to 60 feet anyway, so it's not that much deeper.
Colombia is deliciously hypnotic and spooky, with its towering pinnacles, so the greatest danger is that you get distracted with sightseeing and fail to keep aware of your depth. Check your guages often, and, until you have a much more broader experience base, stay shallower than the DM by a tad (and don't get ahead of him). Remember that you do not have to navigate through swim-throughs if you become nervous, but can swim over and rejoin the group on the other side. Talk to your DM and buddy beforehand, and make sure they are aware you may do that. It is better practice if buddy pairs both make the same choice, of course, so discuss that issue in advance and decide on appropriate hand signals with buddy and DM to indicate if you are going over or through the swim-through.
All four of those dives are very nice ones. You'll have fun if you just relax and practice the same basic skills you learned and demonstrated in your class dives.
There ARE dives I would strongly recommend new divers not attempt, such as Barracuda, San Juan, Punta Sur, Maracaibo, and El Islote, all of which are either very deep (in excess of 100 fsw) or characterized by potentially severe currents.
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