Mask fit, anti-fog, strap setup

The suction test

Testing your gear is vital. You must perform a suction test before every trip to Anilao or anywhere else.

Place the mask against your face without using the strap. Breathe in through your nose and see if it holds. If the mask falls off immediately, you have a leak problem. A good seal is essential because water entering your eyes ruins the experience. I remember a trip to Koh Tao in 2016 where my cheap mask leaked constantly. It felt like swimming with a bucket on my face.

Don’t trust the strap alone. The strap only keeps the mask in place while you move. If the silicone skirt does not match your facial structure, no amount of tightening will help.

Choosing your mask shape

Face shapes vary wildly. You need to find a frame that matches your bone structure.

Single lens masks provide a wide view. They often feel lighter on the nose. However, twin lens designs are frequently more rugged for rocky environments. I noticed this while diving in Komodo back in 2019. The currents there can push you against coral if your gear fails. You need gear that stays put.

Some people have flat faces. Others have deep eye sockets. Low-volume masks are great for advanced divers because they require less air to clear. If you are still doing a PADI Open Water course, a higher volume mask might be easier. It makes clearing water much simpler.

Solving the fog problem

Fog is a massive nuisance. It blocks your vision entirely.

New masks have a thin silicone film left from the factory. You must remove this layer to prevent fogging. Many divers use a lighter to carefully melt this film away. This process is risky because you might burn the silicone. I prefer using non-gel white toothpaste for this task. It is safer and very effective.

Apply the paste to the inside of the glass. Rub it in with your finger for 60 seconds. Rinse it out with fresh water before you enter the ocean. You can also use dedicated products like Sea Drops. These cost about 12 USD per bottle. They work well if you apply them right before your dive.

Spit is a classic method. It is free and works in a pinch. Just coat the glass and rinse it quickly. This creates a thin film that prevents water droplets from sticking. It is not pretty, but it works.

Strap tension and leaks

Strap tension is a delicate balance. Most beginners make one specific mistake.

They pull the strap too tight. This causes deep pressure marks on your skin. It also changes the shape of the silicone skirt. When the skirt deforms, water leaks in through the sides. I saw many students in Cebu doing this in 2021. They thought tightness equaled a better seal.

Loose straps are also bad. A loose strap allows the mask to shift when you swim. This movement breaks the seal against your skin. You should feel the mask sitting lightly but securely. The strap should sit high on your head, not just on your forehead. This prevents the mask from sliding down your nose.

Mask volume and clearing

Volume matters for comfort. It affects how you breathe through your nose.

Low-volume masks are popular among technical divers. They require very little air to clear water. If you take water into your mask, you must exhale through your nose. This pushes the water out from under the skirt. A large mask requires a huge breath to clear. This can be difficult if you are stressed or deep.

I prefer masks with a volume of less than 50 cubic centimeters. This makes clearing easy at 25 m depths. If you struggle with buoyancy, a large mask might add unnecessary stress. Keep your gear simple and efficient.

Material and durability

Silicone quality varies between brands. Cheap masks use low-grade materials.

High-quality silicone stays soft for years. It conforms to your face easily. Low-grade silicone becomes hard after 6 months of sun exposure. This hardness causes leaks because the material cannot bend. I once bought a 15 USD mask in a local shop. It became useless after only three dives because the skirt cracked.

Tempered glass is a non-negotiable requirement. Never buy a mask with plastic lenses. Plastic scratches easily and provides poor clarity. Tempered glass resists scratches and handles pressure changes well. Always check for the ‘T’ stamp on the lens. This ensures it meets safety standards.

Maintenance and storage

Care extends your gear life. Treat your mask with respect.

Rinse your mask in fresh water after every dive. Salt crystals can degrade the silicone skirt over time. Do not leave your mask in a hot car. Heat is the enemy of silicone. It makes the material brittle and prone to cracking. I keep my gear in a cool, shaded area in my bungalow.

Avoid touching the inside of the lens with oily fingers. Sunscreen and hand creams cause fogging issues. They leave a residue that is hard to clean. If you use heavy sunscreen, wash your hands before handling your mask. This small habit saves a lot of frustration.

Check your strap for cracks annually. A broken strap can lead to lost gear. If the strap feels stiff, replace it immediately. Most straps cost around 10 USD to replace. It is a cheap insurance policy for your vision.

If your current mask leaks during every descent, go to a local dive shop and perform the suction test with three different models before buying a new one.

Frequently asked questions

How do I know if my mask fits?

Place the mask on your face without the strap. Breathe in through your nose once. If the mask stays stuck to your skin, it fits well.

Can toothpaste really stop mask fogging?

Yes, non-gel white toothpaste can remove the factory silicone film. Use a small amount and rinse thoroughly before your first dive.

Is a single lens mask better?

Single lens masks offer more field of view because they have less frame in the middle, but twin lenses are often more durable for heavy use.