Sunday, July 12, 2020
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Decisions decisions.. Cetma or Alchemy fins..


Well-Known Member
Apr 12, 2016
So i have a bunch of money that got left over the past months and i was thinking of upgrading to some higher end carbon blades while i can.

Another reason is that i've been spearfishing alot the past 3 years and i feel like i would like to put more focus on just the freediving part than I've done before and make it atleast 50/50 freediving/spearing . I'm probaly also gonna complete my courses and might go for a instructor course in the end.

I've been kicking a pair of fins4u carbons for about 2 years now and while they have been a pair of real workhorses 3-4 times a week and very durable after surviving after being beaten around reefs and rocks as much as they have.
However they are pretty stiff for being mediums, which the maker also states on their website. In hindsight i wish i went for the soft since I can't really work on getting proper kicking technique with these since they are too stiff and will exhaust my legs pretty quick if i don't use smaller shorter kicks.

When spearing the average depth I dive is 15-22 meters, occasionally 25-30. Hower i want improve on this alot so I'm looking for fin with a stiffnes that would be kind to legs and ankles but still with power enough to bring me up from 40-50 meters.

Just some facts that might play a role in the topic; My weight changes up/down a decent amount every year, at this time of the year when the rainseason/monsoon have been around for many months i will dive and exercise less and my weight will increase to around 75-78kg. While in the end of diveseason i will be at around 71-73kg.

I'm now trying decide whether to go for alchemy v3's or Cetma mantras but there are some questions and considerations that makes a decision harder than I thought it would be.

So first to the Alchemys, what makes me hesitant to these are choice of footpockets. I currently use the pathos fireblades in size 40-41 and they fit perfect lengthwise but they are too wide at the insert/around the heel. I use 3mm socks and i can fit two fingers in when having them on, with 5 mm socks they fit better around the heel but it will be too tight on the top of the foot. Solution to this has been finkeepers which works OK but I still have that wide gap around the heal and my heels still rise up more than I like from the bottom of the footpocket.

The other footpockets that is recommended for these fins are mares razor, but apparently they are heavy and have chunky rails which is best to dremel down to soften them up. Just kind of sucks to have to modify them like that and risk overdoing/damaging them so you to deal with waiting time of ordering another pair.

The v3 30's is another option because they come with the new c4 pocket which doesn't seem as wide as the pathos fireblades. However it's 100+ euro in price diffrence for a bit longer blade and 300 footpockets. And I guess the 300's doesn't fit the regular v30's because of the diffrence in blade angle.

Also not sure if I should go for mediumsoft or soft stiffness. Feels like mediumsoft might be the best compromise for both spearing and pure freediving.

The Cetma Mantras is the other choice which are the ones I'm leaning closest to currently.
The sizing of the footpockets seem more close to how my foot shaped according to their sizing chart. A 41-42 would leave me 1 cm space from maximum length and also 1 cm from maximum width.

They are also a bit longer than the v3's but at the same time a bit cheaper and alot cheaper than the v3 30's. Hower they seem thinner/more fragile than the Alchemy.

The biggest concern I have regarding these are the stiffness. The mediums seem to be pretty soft compared to other brands mediums and it makes me worry about soft being to soft or the mediums turning out to be stiffer than expected.

Anyone here who tried both fins and can give some second thoughts and recommendations?
Last edited:


New Member
Jul 29, 2019
Hi, i had similar questions when I was purchasing my fins. I did purchase cetma competition mantras with s wing pockets and very hapy with them , stiffness medium. I am 95kg. Footpockets are the most comfortable and best fitting for me. Pathos been too wide at front and heel and too low at instep i did try immerse which did not fit at all and sporasub which were not bad but s wing is another level head and shoulder above. Also I did order alchemy pro fins for travel and they have no problems gluing cetma footpockets for me. All I need is to post it to them directly which I did when ordered from cetma. Hope it helps - The Worlds Largest Community Dedicated To Freediving, Scuba Diving and Spearfishing


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