How to: choose a monofin (for the Pool)

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Sanne swimming with the Leaderfins Hyper mono-fin
Sanne swimming with the Leaderfins Flyer mono-fin.

…or actually how we think we should choose a mono-fin. As Jorg Β and I were training last week, we tested a few different kinds of mono-fins. We wanted to see the difference between the fins in areas like;

  • if they were comfortable
  • how they performed
  • what the efficiency is
  • how the balance is using the mono-fin

The tested mono-fins were three kinds, two were from Leaderfins and one was from Special fins.

  1. Leaderfins Freediving Sport
  2. Special fins ‘Dolphin
  3. Leader fins Flyer


The first thing to notice when putting on a mono-fin is the difference in foot-pockets. All three mono-fins, differ very much in how comfortable they are when you put them on.

  1. The least expensive one form Leaderfins, wasn’t all that tight around the feet. Supposedly making it a good to wear fin as it goes easy on the feet, but the thing to note here is that your feet are in direct contact with the foot pocket – although so it feels.
  2. The special fins mono-fin was already a bit more comfortable as the foot pockets are surrounding the feet with a layer of rubber. They have a somewhat tighter fit and in this part of the test they feel they nicest to wear.
  3. The Leaderfins Flyer mono-fin has extra tight foot pockets to improve the efficiency when bringing the freedivers power to the water to propel. This is also what you immediately notice when putting them on your feet. They are as tight as you can expect them to be. In the beginning I could only wear them for 20 minutes or less. Over time this seems to be a thing you can get used to, but this is a process we’re still going through.


Specialfins - Dolphin
Specialfins - Dolphin

Testing the performance comes down to how we feel and see each other perform a good technique with the fin.

  1. For me personally the Leaderfins Freediving Sport was the lesser one of the three, because I could totally not feel that any the effort I put in, was going anywhere… In my experience this fin was just dangling from my feet and making me all unbalanced and Jorg’s feedback on the technique was even worse. The other way around Jorg could say the same and I spotted the same lack of technique in Jorg’s runs.
  2. This mono-fin already has a way better feel and with proper training it is feasible to improve your technique and thus your performance. For me personally I think I still better of with a slightly harder blade, Jorg could already find a good balance and technique with this fin.
  3. The weight in the arch of this mono-fin -about 5 kilograms – makes it easier to control the performance, because once the proper motion is executed the weight is behaving somewhat like a damped movement. Not that the amplitude is dampened, but actually no real peaks and no excessive movements. As if you’re movement is filtered.Β  Once the fin is set into motion, it feels as if your guided into your next stroke either up or down.

When it comes down to how much force you put in compared to the output that the blade delivers we’re talking about efficiency to see where the least amount of energy is lost into things like footpocket clearance, blade surface, stiffness of blade and rubber.

  1. As I mentioned above in the comfort, this mono-fin has a minimal layer between your feet and the blade. Furthermore the rubber used on this fin is supple and the blade is soft. For me these factors are not ideal and proved to be making it hard for me to effectively make a full mono-fin movement. Overall it felt like having to really put all the energy into the blade through the tip of my toes. Which made my feet and ankles hurt after only 4 lanes. Jorg could make easy movements with these fins, but had to agree that you have to put energy into the fin with your toes.
  2. The footpockets on this mono-fin are already a big improvement compared to the first one we tested. You feel that more power and energy is put into the blade, but for me the stiffness of the blade is slightly on the soft side. We tested different kinds of techniques on this one; kick-glide & constant kick. Overall Jorg and I both have a good impression about this mono-fin, but the somewhat loose foot pockets and supple rubber still makes us believe that not all of our power was transformed into propulsion.
  3. With the 2 preceding mono-fins we’ve experienced foot-movement and supple rubber and soft blades, but this type of mono-fin really excels on the area of efficiency. The arch with added weight, keeps the motion going. The foot pockets are really a tight fit, which makes it feel like all energy put into it is transformed into propulsion. The rubber used for the pockets and arch are pretty rigid, combined with a stiff blade makes this feel like you’re being efficient when executing the mono-fin movement.


Leaderfins - Freediving Sports
Leaderfins - Freediving Sports

Swimming with a mono-fin is particularly difficult when it affects your balance, Jorg and I witnessed this effect with Sandi Bitenc’s world record attempt last week.

  1. In my experience with this mono-fin the balance was very hard to find, because of the toes having to put in all effort. The thing I spotted when Jorg was doing his test runs with this one, the movements to the side were very much present, not looking like a controlled motion at all. This also influenced the position of the upper body making it tilt and roll during the test runs.
  2. For me the balance with this fin comes down to putting more exercise into the technique. I dislike the somewhat soft blade, which makes it less controllable for me. But this can also mean a lack of experience in mono-fin swimming from my side. Jorg seems to get away with this mono-fin easily and makes the movement look controlled and balanced.
  3. For me this mono-fin was first up in the test runs, making my previous judgments very clear and pointing out that I really have the need for a rigid mono-fin and a stiff blade. From the start this mono-fin makes a normal movement and does not tilt me or roll me over when applying force. After exchanging thoughts, Jorg’s experience after he tested the other two fins was almost the same as I had felt it. Of course we have to put more time and effort into our technique, but this goes for all the mono-fins.


Leaderfins - Flyer
Leaderfins - Flyer

To conclude our small test with these types of mono-fins, is that we’re now continuing with the Leaderfins Flyer mono-fin. Not because of the comfort, but of excelling in all other test areas that really matter when doing a distance performance in the pool. Our conclusion on the test areas we picked is that we’ve setup a pretty good test method to find a fin to continue our training. Having tested the different mono-fins, makes us realize that technique is everything with freediving with a mono-fin, not because we’ve just started using the mono-fin, but because efficiency is really all that matters and makes a mono-fin excel the bi-fins for most freedivers.

Next review/test

Leaderfins - Hyper
Leaderfins - Hyper

We’re very keen on testing a mono-fin which features the foot pockets that are placed on the mono-fin blade more, like the Leaderfins Hyper. As we refer to them as rocket-pockets ;). These are more likely to have a better angle for your feet Β and the fit should be better, but still in the efficiency area. All these are assumptions are based on feedback we received from the freedivers who already wear them. This will be a topic for the next test/review we do in our quest into choosing a mono-fin for the pool.

15 thoughts on “How to: choose a monofin (for the Pool)”

  1. Hi,

    I’d be interested to hear how you would describe the currently extremely popular Waterway Glide fin, that Daan, Arjen and I have. I like my fin very much because it is rather soft, Arjen’s fin is even softer and Daan’s a little harder (medium stiffness). I think you would fall in love with Daan’s fin immediately!


  2. @Eric,
    To have a say on that, I’ll have to set up a meeting with you guys and kindly ask you if I may test one of the mono-fins. Which I would really appreciate as you don’t go buying them just for the fun of reviewing them πŸ˜‰

  3. Hi
    Great that somebody does a monofin test, but I would suggest you do it a bit more tehnical. I know it is hard but if you want to compare the results with later test you should set up a few standard test that would be a little less subjective. For instance do a few test runs (I would say at least 10 lanes with every fin), try to swim with the same tehnique and count the strokes and time the laps. Then you also have to work out a point sistem for every test you make so you can compare with later tests.

  4. That is a great idea SanSan. At the moment we were just blogging our experience in how we were choosing our own way to follow. I will discuss this with Jorg as well and see what we can come up with.

    It’s a challenge to find a good scoring system, as some of the aspects do come down to; how a single freediver perceives/experiences it.

    All suggestions are welcome, like your suggestions. Thanks for your comments.

  5. @Sanne
    I know that a great portion of the score will still be subjective and I also think it is a good thing to have a personal comment on every fin. To get rid of subjective mistakes you could try and get more people to test and give them a questionary to answer. If you have enough people you can maybe even loose the top and bottom score and get an average from the rest. You could also try and set most common types of fin users (as you mentioned you like stiff fins, others like soft more etc), and then also have scores from souch groups for every fin. This means a lot of work and a lot of people to participate but I think this would realy help people to identify the monofin that suits them best.

  6. @SanSan this is evolving to a great initiative! It’s also why we initially started writing this story. It’s hard to find any directional information on how to choose a monofin or other materials (I’ve already written more how-to’s).

    I’ve already jotted down a few methods and things to test, that might give a good perspective. But this also includes the use of underwater-video material to use for analyzing.

    I like your idea and I think if we could find the system you’re describing in your earlier comment, it’s easier to involve people, independent of their location. I reckon we could use an experienced monofin user view as well to have a critical look at the things to test, so maybe you’re interested on helping out as well?

  7. @SanSan
    No problem, I know of your time limitations. I’ll setup a document on how we would like to test/review the mono-fins and when it’s reached a more finalized state I’ll pass it to you for review to see if I left any important details out.

  8. Hi all,
    I am just about to finalize my order for my first monofin. I will mainly be interested in doing constant weight with fins, but of course doing training in the pool during winter too. I’m only in this for the fun of it, no ambition to compete or break any records. I was advised that a (angled, full-pocket) Waterway Nemo would be better than for example a “flat Model 2”, but I have also heard that the angle of a monofin might cause some loss in efficiency at depth, when turning? What is you take on it? I am leaning towards the (all Leaderfins models) Freediving Monofin “Freediver” or Freedivin Monofin OMER?

    Fullpocket is what I want though, as long hours in the lake might make this the more comfortable choice, and as I said, it is a long way until I am going to hit 30 meters etc…

    ANY experience or recommendation greatly appreciated! πŸ™‚

  9. Hoi Jonas, I am for sure not an expert but since no one else answered I’ll give you my thoughts…

    I owned a monofin with an OMER footpocket and found out it did not suit my feet at all. The OMER footpocket is very rectengular, wide, and quite hard. With thick socks it was ok but not very efficient (my technique sucked a lot back then, it still does but less so). In the pool the pockets were much to wide period.

    I own a Hyper Pro and a Waterway glide which both have an angle and the footpocket itself isolates you for the most part from the cold water. The general recommendation is that for CW you go for a medium stiffness and for the pool somewhat softer. This is mostly to give you enough power when coming back up. For getting a good technique opinions vary also. Some say take a hard blade because you will feel much better in your legs when the force comes incorrectly from your knees. Most however these days go or a blade (in the pool) that is a soft as you feel comfortable with. This is what I did and I probably need another fin when I would dive deeper (now to about 40 meters) but for now it’s fine.

    I bought cheaper fins before and they have there place but I wished I’d sooner spend the money on a soft fin with as much angle as they sell with no full footpocket.

  10. Hi Eric, many thanks for that. I received valuable input as well during the order process from Maksim at – at the end of the day I am taking a bit of a chance with my first order, but at the end of the day the options are limited as there is no where here I could simply try lots of various designs before ordering, plus I am quite excited about having it soon.
    It will give me some first experience and find out what changes I require for my second and sell this one one perhaps. Or maybe I am going to be lucky πŸ™‚


  11. Hi,

    I thought your question was a few weeks old. Seeing that it’s from yesterday my reply is a bit premature.

    But anyway.. please tell us what fin you ordered and what the factors were that made you decide on that specific model.


  12. @Eric
    Thanks for adding your experience about full pocket monofins. As I already explained in the story above, I’m still to try out a full pocket monofin. Maybe next tuesday I could try out yours for a run πŸ˜‰

  13. Hi Sanne,

    I sold mine as soon as I could. I now own an ultra soft WW model 1 (or 2, biggest blade anyway), a soft Leaderfins Hyper Pro (excellent fin, but needs a lot more angle for me) and a soft/medium Waterway Glide (nice fin, would like a bit more angle though and perhaps a bit softer too)

    You’re welcome to try any of them next tuesday.


  14. Hi Eric & all,
    I ordered the Leaderfin “Freediving Monofin Freediver” with Wings, so it basically looks like their “Freedivign Monofin Wings” model. Except it has a few more tiny “rubber ribbons” on the blade. I’m off diving in Turkey on Saturday and will take the fin along for a test in the pool and hopefully the sea – the foot pockets are quite rectangular and wide, so I certainly need some socks – or “inlay-soles” (Superfeet) seem to work to jam the foot nicely to the footpocket – not sure about the heel though and will therefore get some 3mm socks asap. I’ll put a proper report on my website when I’m back πŸ™‚

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