Tails and monofins: what they are and how to look after them

A mermaid tail looks like one piece, but it is really two: a fin that does the work, and a skin that makes it beautiful. Understanding both helps you swim better, stay safe, and choose well if you ever buy your own.

You do not need your own tail to learn with us. A tail, fin and mask are lent to you for every lesson.

How a tail is made

• The monofin is a single blade with two foot pockets, so both feet kick together. It is the engine.
• The skin covers your legs and the fin. It shapes the fluke, the tail's end, and gives the look: colour, scales, fins.

Royal Life Saving Society Australia draws the same line. A full tail encloses the body from the waist down and keeps the legs together. A monofin on its own holds only the feet. That difference matters for safety, which we come back to below.

Tail skins: fabric, neoprene and silicone

Fabric

Most people learn in a fabric tail. Makers use stretch fabrics such as four-way spandex or the thicker, opaque scuba knit. A fabric skin slides over a separate monofin, so each skin is cut to match a particular fin. Fabric is light and quick to put on. The trade-off is that it wears out sooner than heavier materials.

Some fabric tails add internal pieces that hold the monofin in place, so the fluke keeps its shape.

Neoprene

Neoprene sits between fabric and silicone. Dive training writers describe neoprene and neoprene-silicone hybrids as lighter than full silicone but more realistic than fabric. Professional mermaid Linden Wolbert keeps sequinned neoprene tails for pool performances, so no sequins are lost in the sea.

Silicone

Silicone tails are sculpted, painted and usually made to order. They are works of art, and their weight reflects it. Makers quote different figures: one gives 16 to 20 lb (about 7 to 9 kg) for its own tails, another says 20 to 50 lb (about 9 to 23 kg) depending on design. Linden Wolbert's first silicone tail weighed 35 lb, and her current one 50 lb.

Most silicone tails have the monofin sealed inside. That gives a seamless look, but you cannot simply slip the fin off. Getting in, out and around takes strength, technique and usually help. Makers themselves describe these tails as for experienced swimmers and professionals. A silicone tail cannot meet the "remove it alone in seconds" check below, which is why silicone is for experienced mermaids with a dedicated safety watcher.

One maker, Finfolk, makes a point every buyer should remember: a tail is not a swim aid or a lifesaving device. Whatever its material, it makes swimming harder, not easier.

Monofins

Blade types

• Plastic mermaid fins. Light and affordable, and shaped to sit inside a fabric skin. They may not last as long as other materials.
• Rubber blades, used on some monofins.
• Fibreglass or carbon. Freediving and finswimming monofins, with blades whose stiffness changes towards the edge. They give strong propulsion and suit trained swimmers.

Monofins have a sporting history of their own. They were developed for finswimming from the mid 20th century, and by the end of the 1970s swimmers using them had broken every finswimming world record.

Stiffness

Softer blades are more comfortable and forgiving, which is why beginners start on them. Stiffer blades push more water with each kick, but they ask more of your legs, your core and your technique. Moving to a stiffer fin is something to do with your instructor, not on a whim.

Foot pockets

Foot pockets come in different designs. Some are fully moulded, some open at the heel, and some use straps. Whatever the design, they should hold your feet snugly without pinching, and they should not rub or cause blisters.

How a tail should fit

• Snug, not tight. A loose skin creates drag and bunches around your knees. A tight one restricts the kick and gets uncomfortable fast.
• The right fin for the skin. A skin made for one monofin will not sit properly on another.
• The right size fin for your feet. Your heels should not lift out with each kick, and your toes should not be crushed.
• Length you can manage. Longer flukes look dramatic, but they are harder to control. Shorter ones are easier to steer.
• Measure, then check. Use the maker's measuring guide, and try the fit at home before going near water.

The most important safety feature: you

The single most important thing about any tail is that you can get out of it yourself, quickly, in the water. Royal Life Saving Society Australia asks that anyone in a tail can free their feet from the fin without help and reach the side, a ladder or shallow water.

For a fabric tail with a separate monofin, getting out usually means freeing your feet from the foot pockets, then sliding the skin down past your hips and swimming clear. Practise this in standing depth, with someone watching, until it is easy and quick.

Before trusting any tail, check:

1. Can you remove it alone, in the water, in a few seconds?
2. Do your feet slip out of the pockets when you want them to, but not by accident?
3. Is there nothing you cannot reach, such as a fastening at the back?
4. Does it bind your legs more tightly than you need? Royal Life Saving Society Australia advises avoiding tails that do. Ordinary fins, which leave the legs free, may be a better choice for casual play.

For children, one children's tail maker, Fin Fun, advises that children aged 5 and under, or under 20 kg, should not use a tail with a monofin. Our guide for parents covers tails for children in more detail.

Looking after a tail

Good care keeps a tail safe as well as pretty. A cracked fin or a torn seam can fail when you least want it to.

After every swim

• Rinse in fresh water, soon after you get out. Lukewarm water lifts salt more easily than cold. Rinse inside the foot pockets too. Chlorine and salt both wear materials down.
• Dry in the shade, completely, before you pack it away. Sunlight breaks down rubber and fabric.

Storing it

• Lay the fin flat, somewhere it will not be stepped on.
• Never stand a monofin on its blade against a wall. It bends out of shape.
• Keep it cool and dry, away from direct sun. In Singapore's heat, that means not leaving it in a car.

In the pool

• Do not stand or walk on the blade, and do not push off the wall with it. Push off with your feet instead.
• Keep it off rough surfaces. Pool floors and edges scrape fabric and silicone alike.

Checking it

Before every swim, look over the fin for cracks, stress marks or tired rubber, and check the skin's seams for tears. If you find damage, contact the maker before trying to repair it yourself.

Silicone needs more

Silicone is durable, but it needs regular care. Rinse it after every use, keep it away from anything sharp, and follow the maker's own instructions for cleaning and storage.

Thinking of buying your own?

Many students do, once they have learnt what suits them. Before you buy:

• Learn in lent gear first. You will know far better what you want after a course.
• Start light. A fabric tail on a soft fin is the right first tail for almost everyone.
• Buy from a maker with clear sizing and safety guidance.
• Plan where you will use it. A pool, with someone watching you, and never alone. See Never alone and Pool or open water?
• Avoid loose glitter and plastic scales that can shed into the water. See Respecting the water.

We do not sell tails at present, so this is honest advice rather than a sales pitch.