Being a freediving instructor, you might guess that I am somewhat thoughtful about the fins I use for diving and snorkeling. This is certainly true, and for serious freediving, I can tell you a lot about the souped-up, $600 carbon fiber fins with all the bells and whistles. And while these fancy fins do have their place, for general snorkeling and diving, simple is just fine, if you know what to look for.
The most important feature with respect to a fin is the FIT. A cheap fin that fits your foot well is much better than the latest multi-hundred dollar dive techy product if it doesn’t fit well. Imagine running in fancy fitness shoes that don’t fit. You wouldn’t do it, and the same goes for fins. The fit is the interface between your foot and the fin, and this is what matters, because that is how energy is transferred from leg to fin. This energy transfer is also why a simple fin with a foot pocket is better than a buckle on fin (designed to go with dive boots). Remember to account for the appropriate thickness of fin sock when trying a fin for fit.
A word about split-fin technology. I don’t think the feature is worth the price. Split fins seems like an invention for the gear heads, as a way of justifying a $100+ price for an item that should cost you less than $50. It is true when you start kicking with a split-fin, particularly from a stand still, the kick does seem to be more comfortable. This is because the split in the fin is giving way, so that it doesn’t bend your ankle as much. However, this benefit comes at the expense of power. The split-fin can make a session of kicking more comfortable, but because of the split, when you need power, it will be hard to get it. You can check the net for countless stories of people getting caught in currents and being unable to escape because of the lack of power in split fins (which is inherent in their design).
Because of the additional stress/ankle extension that comes from kicking from a stand still, I think it is perfectly fine to have a small amount of split in a fin, to make the initial kicks easier. Another good solution I have seen for this are the small vent holes in the Aeris Velocity Full Foot Scuba Fins. I highly recommend them. They are light, cheap, simple fins, and the small vent holes work well for making it easier to kick. I have done many freedives of more than 100 feet (30m) in them, which I think is a great testimonial. Keep it simple.
Another related tip, which not too many people are aware, of is the use of an item called the Fin Keeper. They are great for snorkeling or diving. Fin keepers are cheap rubber straps that hold the fin onto your foot, kind of like large rubber bands. If you have them on, the fins will stay snug on you feet, and they won’t fall off. This is particularly useful if your fin is a tad too large.
Finally, good Fin Socks are a must for keeping your feet warm and protecting your feet while walking on rocks.
Aeris Velocity Full Foot Scuba Fins $25-50 on Amazon
Trident Fin Keepers ~ $6 on Amazon
Tilos Fin Socks ~ $15 on Amazon