Altered States: Just add water. And a lot of salt.

If you solve problems using code you understand the storm that is within. It’s Tron meets The Matrix. Everything in your head is fighting for resources, algorithms crunching numbers, pointers going astray in your stack and the garbage collector nowhere in sight to clean the mess up!

Monkey Brain

There are solutions to this madness. The process is called calming your monkey brain typically through Meditation. But Meditation isn’t for everyone. Many have tried and failed because let’s face it, the classic method of Meditation sucks. It is a pain in the back side to sit there for an extended period of time trying to cut out all the distractions of the growing pain in your back to the ~70db pollution hitting your auditory sensors. Why do we still encourage meditation the old school way when there are far easier and more effective methods to calm the monkey mind?

John C. Lilly

In 1950s we knew little about sensory isolation. Many great minds speculated that insanity would follow any attempts to turn off our core senses — visual, auditory and kinesthetic. All with the exception of 1 badass scientist, John C Lilly. He proposed that if one could isolate the mind from external stimuli one could experience heightened sensory perception. He devised the first isolation tank, a dark soundproof tank of warm salt water in which subjects could float for long periods in sensory isolation. He proved his hypothesis right. And the rest is history. Google John C. Lilly to learn more about his work.

John C. Lilly built a modern day version of a meditation tank.

The Architecture of an actual Isolation Tank aka Floatation Tank
The Architecture of an actual Isolation Tank aka Floatation Tank

Today, such isolation tanks (aka floatation tanks) are found all around the world. From spa centers using it to relax the body to sport centers to expedite recovery (eg. Australian Institute of Sports) and to private use to explore the mind like John C. Lilly and myself do. Yet very few people know about it. So let me tell you more.

Where it all began for me

I have been “floating” starting in Australia since 2008 and later in the US. I was inspired by the 1st episode of Fringe. Dr Bishop used an Isolation Tank (also known as sensory deprivation tank) to connect Olivia and Agent Scott’s mind to tap into the dead agent’s mind to retrieve information related to the case. Low level protocol stuff. Yeah pretty insane utility but what if. So I took the red pill and went down the rabbit hole.

You may hear the word “floating” being used. This reference is more rosey but means the same thing; isolation tank experience. You float inside the isolation tank like a cork on water due to the high concentrate of epsom salt. If you have been to the Dead Sea you will know what I mean. A secondary benefit of the salt is muscle relaxation. Epsom salt has been used for centuries for muscle aches.

The Apollo ELV Float Tank — #1 Floatation Tank
The Apollo ELV Float Tank — #1 Floatation Tank

As you can see from the pictures, the cause creates an effect ~20mins into the journey you will feel like a brain floating in space. Disconnected from your auditory, visual and kinesthetic senses. This heightens the mind’s processing ability so you can begin exploring your private sea, your mind, in a conscious state.

At the end of a 1 hour floatation session you will feel like your body and your mind got a massage.

The Theta State

The goal with both meditation and floatation is to reach the theta state. This is a state where you can consciously listen to your subconscious mind. Or let’s put it a different way, experience hallucinations without drugs, insanity or sleep. Monks train years to do this through meditation while staying consciously awake. Your body does this naturally every night but you consciously switch off aka fall asleep. Recall those auditory or visual flashes you get before your off switch kicks in and you fall asleep? That’s a glimpse into theta state. In an isolation tank you are consciously awake observing your subconscious mind. Most of the time. No years of training required. For me it turned out after 3 floatation sessions I was hallucinating baby!


Our subconscious mind is a powerful supercomputer (no surprises there) which constantly gathers, calculates, builds patterns & connections faster than we can consciously observe (process). I think this is a natural safe measure so we don’t go insane. Now imagine being able to tap into this wealth of stored info for a bit. You know when you sometimes get a gut feeling — I believe that is the output from all the processing bubbling their way to your conscious mind. I use the isolation tank to tap into this and get my answers faster then waiting for them to bubble to the top.

Why isn’t this a Company benefit yet?

Floating should be a company benefit. Heck, even more.. a company policy. If an employee is having a hard day for whatever reason (personal or business) just send them to an isolation tank for 1 hour.

That’s empathy right there;

  1. Identifying your employee is experiencing some distress and
  2. Do something about it that will have a far reaching impact on their emotional state than a 1:1 talk or sending them home.

We are human creatures with emotions. Fact. Ignoring this fact in my opinion is narcissism. If you have empathy do something constructive and help your colleague.

Finished a big project? Scrap the default lunch mode celebrations — take the team to a Zen center and have them all float. Afterwards you can all reflect on the achievement while sipping camellia tea. Better?

Run an experiment

There are float centers up and down the Bay Area and all around the world. Google it. Run an experiment with your team or yourself floating at least 5 times — 1 every week. That’s a tad over a month. Measure the experiment so you can quantify it and remove any cognitive bias. Then reflect on your calmness, clear head, relaxed nature and more empathy. Let me know what you find. There’s nothing more powerful than experiencing the power of this amazing mind and body hack for yourself.

Float already!

Few final snippets before I wrap this up.

Be vigilant about the tank

The Tank you choose needs a good ventilation system. High temperatures will race your heart just like a steam room does. It will become extremely unpleasant. I had it happen to me. Reached 144bpm and it was the worst experience ever. The Apollo ELV Float Tank is the best tank I have ever experienced. It is the Tesla of Tanks!

If its important, don’t sleep on it

Float. You will get more insights.


Float. The Epsom salt does wonders to your skin and muscles. Afterwards, you will feel super relaxed. And if you fall asleep from exhaustion inside the tank you will be fine floating like a cort. Should you tip over, the high concentrate of salt will burn a hole in your head *j/k*. It will sting tho.

At a minimum, start with 3 float sessions

It will take some time for you to learn how to fully let go and relax your body while suspended like a cork. Only then will the mind let go.

Installing a tank at your company?

If you were inspired by what you learnt here and decided to install a tank at your company then please invite me over for a float session. Or if you need help or have questions please reach out.

More juice on Isolation Tanks & Sensory Deprivation

Happy Floating!

PS. This article also appears on

~ Ernest

Floatation (isolation) Tank – indepth and upclose

Welcome back for more juice on Flotation Tanks. If you have not read my previous post “Floatation (isolation) Tank – fringe science?” then I highly recommend you go there first and read the introduction to understand what they are, the benefits of the experience and see some screenshots of tanks I’ve been in, in Sydney (Australia) and San Francisco (USA).

Let’s delve inside – how to temporarily turn off your 3 senses

Isolation Tank specs

  • The tank is not airtight – it is designed to let air in via the roof.
  • It’s pitch black inside. Used to disassociate your visual senses from the environment.
  • The tank environment is humid – 37° celcius (99° Fahrenheit) – your body’s temperature. Helps with disassociating your kinestatic senses from the environment.
  • Around 10 inches of water in the tank with 800 lbs. of Epsom Salt dissolved in it. When you lie back you will float like a cork. Your ears will be under water. All places I’ve been to provide you earplugs. Use them to cut out all remnants of noise. That’s how your auditory senses are disassociated from the environment.
  • Keep the salt out of your eyes. Once inside do not rub your eyes or touch your face – the salt is very strong and even a small drop will sting. Make sure you have a towel near the tank to dry your hands before touching your face / eyes. The same goes for any cuts you have on your body. Make sure you cover them up with Vaseline or similar to stop the salt from entering the wound.
  • At the beginning of each float set an intention for what you would like to accomplish during your float. Then enjoy the float – the rest of the journey your mind will take you through.

What to expect during a float

The following is based on my experience. Each experience varies but they all share similar stories.

  1. First 20 minutes is calming down your mind and relaxing your body. First timers will find it strange to let go at first because being buoyant is a strange feeling and letting go of tension without touching anything in the tank is even stranger – yes you do float in the tank without touching the bottom or the side walls. When the tension pain is gone that’s when you have fully let go (especially neck muscles).
  2. Concentrate on your breathing – in through your nose and out through your mouth. Try this approach, 4 seconds in, hold for another 4 seconds and 2 seconds out (I will cover breathing techniques in a future post and why doing it correctly is super important). Also try to resist moving or scratching an itch. During the start of a meditation session when your senses are slowly being turned off, your brain will send signals to your body to try to awaken them – this will come through as an itch or a muscle twitch. Resist it for couple of minutes and it will pass. Concentrating on your breathing will also help you with the fight against the “monkey mind”. The monkey mind are random distracting thoughts which rush in and out of your mind.
  3. After 20 (or so) minutes have passed you will find yourself in an open minded state. Your mind should feel clear & open, your body free of tension. This is the relaxed state. Your mind will be in a frequency state called Alpha. A state which you can also use for accelerated learning.
  4. After another 20 minutes (40 minutes into the float) you will enter Theta state. You will be conscious in this state and know when it comes. In this state your subconscious mind awakens and your concious mind will experience auditory and visual hallucinations. You will feel as though you have separated from your physical body and are pure energy, a part of something  greater. Monks practice years to reach Theta in a concious state. Do not resist. Do not get frightened. This state gives you access to insights, bursts of creative ideas – a key state for “reality creation” through vivid imagery.
  5. After 1 hour of floating, soft music will start playing inside the tank. This is your queue that the journey for now has came to an end and it’s time to go back to the reality we call society.

With time you will want to float for longer and longer. I have floated for 2 hours before and even though it may sound like a long time there is no sense of time during a good float. John C. Lilly was known to float for up to 6 hours and trained himself to reach such high states that his experiences are what some people would call out of this world.

I would love to hear your experience in the tank. Please use the comments section below to share your journey in the tank.

Common questions & answers

  1. Q: Will I drown if I fall asleep in the tank?
    A: No. You are always buoyant, floating on top of the water like a cork. Same as the dead seas. If you did roll over, the strong Epsom Salt in the water would instantly wake you up.
  2. Q: I have a fear of being alone in the dark, drowning, not having enough air, claustrophobia, and others
    A: For some the first time might be a bit overwhelming. You can go in and out of the tank as you please. You can use the tank with the door completely open, you can keep it partially open, or you can close it. There is no particular way to use the tank that is more correct than another. Any way you use it, that is comfortable for you, is correct. But once you relax and let go you will experience peace and tranquility and want to come back for more.
  3. Q: I did what you said to do and nothing happened. What gives.
    A: Practice makes perfect. Like anything in life you need to immerse yourself in it and embrace the offering. I recommend you give it a go at least 3 times and each time be open and willing to let go.

Joe Rogan on Floatation Tank

Floatation (isolation) Tank – fringe science?

This is my personal favorite – Floatation Tank. I have been floating from early 2008 and enjoy every session. 1 hour of floating is about the average you need to get the same as 6 hours of sleep. This 1 hour passes quickly, time doesn’t exist in the tank, and when you finish your session you will feel as though you just had a brain & body massage. The feeling is amazing and lasts for most of the day.

What is an Floatation (isolation) Tank?

A floatation tank (also known as isolation tank or sensory deprivation tank) is an enclosed chamber filled with approximately ten inches of warm saturated solution of Epsom Salt. A solution so dense that even the thinnest person floats supine with the entire body at or near the surface of the water like a cork.

Isolation Tank "Classic" model with Ernest Semerda
Isolation Tank "Classic" model with Ernest Semerda

The buoyancy counteracts the effects of gravity, giving the floater a sensation of weightlessness. The chamber is pitch-black and silent. In the absence of sensory input to the logical side of the brain, the left side of the brain synchronises with the creative side (right side) and creates a free state, at peace. In this state, the brain releases vast amounts of endorphins. Most floaters report enhanced mental powers. Virtually everyone finds the experience immensely pleasant.

While the state of relaxation may be deep and profound, the individual’s brain stays dreamily alert. To get technical, the brain gradually shifts from its usual “alpha” state to generate theta waves, the state-of-mind that Buddhist monks try to reach through hours of meditation and years of training. You can achieve this in a matter of minutes just by floating! Best of all, the effects of floatation are cumulative – the more regularly you float, the better it gets.

Why float – the benefits

  • Meditation
  • Reduces stress & anxiety
  • Reduces heart rate & blood pressure
  • Reduces muscle tension
  • Stimulates endorphin production (providing relief from chronic pain)
  • Stimulates Alpha & Theta brain waves (associated with creative insights and meditative states).
  • Relaxation
  • Rest and Recovery – one hour of floating is equivalent to 6 hours sleep. Great for Jet Lag recovery!
  • and in alternative medicine.

In more detail…

Promotes total calm & peaceful relaxation; eliminates fatigue and jet lagimproves sleep; alleviates stress (mental and physical); energises, rejuvenates andrevitalises.

Stimulates left/right brain synchronisation; shifts brain waves from Beta to lower frequency Alpha, Theta and even Delta; creates mental clarity, alertness;increases creativity, problem solving; heightens visualization; deepens meditation; expands awareness, intensifies acuteness of all the senses, accelerates learning.

Enhances hypnotherapy and self-hypnosis; increasesmotivation, diminishes depression, anxiety and fear; facilitates freedom from habits, phobias and addictions.

Improves athletic performance and helps prevent sports injuries, speeds healing process.

Decreases the production of Cortisol, ACTH, Lactic Acid and Adrenaline; increases production of endorphins; quickens rehabilitation and recovery; relieves pain – arthritis, migraines, injuries etc.; boosts immune function. 
Improves circulation and distribution of oxygen and nutrients; reduces blood pressure, pulse, heart rate and oxygen consumption.

The safe sensory isolated environment is naturally conducive to relaxation and peace of mind. Released to float in suspension without the body experiencing the effects of gravity and outside distractions, your entire being achieves levels of rest and higher state much deeper than you have ever previously experienced.

The man behind the magic – Dr John C. Lilly

The first floatation tank was developed in 1950 by the American neurophysiologist Professor Dr John C. Lilly while working at the National Institute of Mental Health (NIMH) in Bethesda, Maryland. Together with his associate Dr. Jay Shirley, Dr. Lilly became intrigued by the question of the origins of conscious activity within the brain. The question was whether the brain needed external stimuli to keep its conscious states active. Lilly and his associate set to work trying to devise a system that would restrict environmental stimulation as much as was practical and feasible. Lilly’s first tank was one in which the floater was suspended upright, entirely underwater, head completely covered by an underwater breathing apparatus and mask (now you know where the producers of “Altered States” got their ideas!). Over the years Lilly continued his experiments with floatation, simplifying and improving the general design of the tank. Dr. Lilly found that he could float in a more relaxing supine position, rather than suspended feet downward in fresh water, if more buoyant salt water was used. Other refinements, such as water heaters with thermostats sensitive enough to keep the water at perfect temperature, an air pump to keep the air in the tank fresh, and a water filter for the re-use of the Epsom salts, were added over the years. By the early 1970’s, Lilly had perfected the floatation tank in much the design used today.

Dr Lilly is also famous for the historical work with Dolphins which has allowed Dolphins to be treated as intelligent & protected creatures.

If you want to read more about Dr Lilly, his amazing journeys into the subconscious & work with Dolphins, check out his books:

  1. The Scientist: A Metaphysical Autobiography
  2. Center of the Cyclone: Looking into Inner Space

Places to float / experience the magic

Here are my 2 favorite floatation centres.

Sydney, NSW, Australia: Bondi Junction Massage and Float Centre – Flotation
Level 1 Royal Arcade, 175-181 Oxford Street
Bondi Junction, NSW, Australia, 1355
Phone: 93877355

Isolation Tank Sydney
Isolation Tank Sydney

San Francisco, California, USA: Atha Floatation
San Francisco, Sunset District,
California, USA

Isolation Tank "Classic" model
Isolation Tank "Classic" model San Francisco

Where else will you find flotation tanks

In the Community: The Australian Institute of Sport, Hayman Island resort, Victoria University of Technology and many more.

In the Movies: Altered States, Fringe: The Complete First Season

Hungry for more? keep reading Part 2 – Floatation (isolation) Tank – indepth and upclose.