A Closer Look at Sensory Deprivation Tanks

To some people, it sounds like heaven. To others, it sounds terrifying.

You float in an enclosed tank in complete darkness while wearing earplugs, stripping away as many physical senses as possible. Sensory deprivation tanks (also called isolation tanks) are dark, sound-proof tanks filled with less than a foot of Epsom salt-filled water.

You’re naked or in a swimming suit and alone. You can’t see, even if you open your eyes. You can’t hear. You can’t even feel gravity, because the salt makes your body float on the top of the water. There’s nothing to do but let go.

It may sound strange, but float tanks continue to grow in popularity, and Boulder has two different float centers: the Isolate Flotation Center and Radi8 Float Studio (formerly Cloudnine Float Center).

Why Float?

The demand comes from the health benefits. Floating is said to help with hypertension, chronic tension headaches, insomnia, PTSD, anxiety and panic disorder, social anxiety, major depression, stress-related pain and agoraphobia.

Although not mainstream, this isn’t just alternative health care drawing from anecdotes. There are peer-reviewed papers and there is clinical research (although limited) backing up the claims, and additional clinical trials are underway in America, German and Sweden.

One 2018 study found even just one session could significantly reduce anxiety. Another study echoed that, also showing improvement in sleep and fatigue.

The most common findings show floating “significantly” reduces stress and increases relaxation. With that, studies have found decreased blood pressure, heart rate and cortisol levels.

Floatation “Reduced Environmental Stimulation Therapy” (REST) has roots in the ‘50s at the National Institute of Mental Health, when doctors wondered how the brain and nervous system would respond to reduced sensory input.

Furthermore, Epsom salt (magnesium sulfate) alone has been shown to help improve sleep. At Radi8 Float, you can actually book an overnight float for $200 and get a full night’s sleep in the tank.

What Happens?

Floating can help you sink into deep relaxation and meditation. You typically spend 90 minutes in about 10 inches of body-temperature water mixed with Epsom salt (although some tanks run cooler or warmer).

When you arrive, you are usually given a tour. Go to the restroom before you float and make sure you have eaten about an hour before or you might get distractedly hungry. Put in earplugs and take a shower with a special soap that isn’t harmful to the tank’s water. Open the tank door and step inside. The water will feel a little different, softer and denser.

Be careful not to shave about a day before floating, and if you have a cut, put something on it or it might sting (although that will fade).

What About (Insert Scary Scenario Here)?

Scared of the dark? You can choose to float with the lights on in an illuminated tank. Some tanks have in-tank lighting, and you can change the colors and control the light.

Claustrophobic? You can leave the tank open. Request a larger tank with a larger opening. Start by sitting near the edge with your head out of the tank and your legs inside. Ease your way in as you feel more comfortable.

Keep your eyes open if it helps. Some people find closing the tank all the way so you have total darkness actually helps with fear of small spaces because you cannot see the end of the tank, so it seems to go on forever. You can go in and out of the tank whenever you want and always have control over the door. You can sit, stand or lie down, leave all the lights on, whatever you want.

Weirded out by the silence? You can request the music of your choice, meditation music or the sound of waves/nature to play over speakers in the room.

Scared of water or can’t swim? You don’t need to swim here. With more than 1,000 pounds of Epsom salt in the water, it’s five times denser than the ocean, meaning no matter what, you will float without trying.

Plus, the water is shallower than a bathtub, you float on your back and you can use an inflatable pillow for your head and a pool noodle under your knees if you want extra support. The pillow can help keep your face out of the water, although your ears will still be immersed. That’s why you are given wax earplugs to put in before you get in the water. The plugs keep the water out of your ears, and there’s ear wash and towels in the room if needed.

Just generally nervous? It might sound scary to feel weightless at first, and sometimes the lack of stimulation can make your brain and senses heighten, as you adjust. But most people calm down quickly.