The tank

The shell

clean it with enzyme cleaner


According to Tim, if you heat the interior roof area of the tank then you'll have no condensation at all.

According to David, sloping the roof is a good idea. Otherwise use bubble wrap. David is also partial to Lilly's idea that condensation is a useful tank stimulus.


Inline or Waterbed

There is a fascinating debate on inline versus waterbed heaters. With an inline heater, you heat the water between sessions as it flows through a pump. Amazingly for an hour session, little heat is lost. Unlike, inline, with a waterbed heater, you constantly monitor and heat the water.

Correct temperature

93.5 is average skin temperature, not body temperature - that's what we heat to

Replacing heater

You can get a standard waterbed heater or buy a heater from David Wasserman of Oasis Relaxation


Tim discusses a thorough protocol for cleaning the tank - IMPORTANT.


  • Chlorine and bromine have no place in a float tank.
  • Hydrogen peroxide is good either dilute food grade like Vicky or just use plain 3% and dump in a whole bottle, like me.

When to change it?

A high use center changes every 18 months. The key to knowing when to change is when the pH cant be maintained.


Why epsom salt

  • See the Epsom Salt Council page for much info.
  • recent data: reduces likelihood of cerebral palsy

Getting and maintaining right concentration in tank

"The Deep Self" gives the guidelines

the hydrometers that are provided in standard battery testers are fine for getting the proper concentration. However Tim knows of a professional hydrometer

We go for a specific gravity of 1.26 and put fresh salts in when it drops to 1.23, with a hydrometer callibrated at 60 Degs F.

Where to get in bulk

Any local store will sell Epsom Salt for 50 cents a pound, so a bulk order is only going to take longer and save you 25 cents per pound. This amounts to 250.00 savings, but lots more hoops and delay since most of these salt distributors deal in much larger quantities and don't really have much interest in a 1000-pound order.

  • PQ Corp sells.
  • Giles Chemical( will refer you to some local distributors who should be able to get you 1000 pounds for 25 cents a pound. I was given these names: Jack Shanks 770-982-4466 and Dan 913-671-7979
  • PICC NY/Kali wont deal in anything less than 1 ton of salt. They will refer you to Epsom Salt Plus 973-471-8919 who deals to the little guy.
  • Univar does not seem to have very good prices.


Petroleum jelly helps

Dissolve the salt well

Before turning on the heaters, make sure the salt is well-dissolved or you run the risk of melting it together or setting the insulation on fire.


Speakers are going to sound OK. Now they will distort the sound through the water. Better is a waterproof mp3 player such as Oregon Scientific. Another good one is SWiMP3.

The Floater

Health benefits


  • salt crystallization

Cuts and Scrapes


  • petroleum jelly
  • pH?


  • 2 hours in a float tank is neurological equiv of 8 hr sleep

Pregnant women

Positive experiences reported

Are you sinking

The tank needs proper specific gravity --- you can be very precise about specific gravity with a good hydrometer.

Shower before entering

get rid of long hair that might clog pump. Remove dead skin cells.


As a business

Recommended books

The public health department


  • "Tanks for the Memories"
  • Restricted Environmental Stimulation: Research and Commentary Medical college of Ohio Press 1987 ISBN: 0-944742-03-3
  • Clinical and Experimental Restricted Environmental Stimulation: new developments and perspectives Springer Verlag, New York 1993 ISBN: 0-387-97962-X ISBN: 3-540-97962-X
  • Restricted Environmental Stimulation John Wiley & Sons, New York, 1980 ISBN 0-471-83536-6
  • The Book of Floating and Megabrain by Michael Hutchison
  • The Deep Self by John Lilly Altered States by Paddy Chayefsky

First/Second/Third/Fourth International Conferences on REST and Self-Regulation

Restricted Environmental Stimulation by Peter Suedfeld

Brain Benders:A Study of Effects of Isolation by Charles Brownfield

CigaREST Quit Smoking Program by Charles Brownfield

Sensory Isolation and Personality Change by Mark Kammerman

John Lilly


Dr. John Lilly's books:

Man and Dolphin

The Dolphin in History [w/M.F. Ashley Montagu]

Lilly on Dolphins:Humans of the Sea

The Mind of The Dolphin

Programming and Metaprogramming in the Human Biocomputer

The Scientist:A Novel Autobiography

The Scientist:A Metaphysical Autobiography {same as above/different title}

The Center of The Cyclone

The Dyadic Cyclone:Autobiography of a Couple

Simulations of God:The Science of Belief

The Deep Self:Profound Relaxation and the Tank Technique

About JCL

John Lilly, so far.... by Francis Jeffrey and John C. Lilly

JCL's Favorites

Pathways Through to Space by Franklin Merrell-Wolf

The Philosophy of Consciousness Without an Object by Franklin Merrell-Wolf

Last and First Men:The Starmaker by Olaf Stapledon

Scientific Research

changed February 4, 2008