Float spas, also known as sensory deprivation tanks, offer a unique environment designed to eliminate external stimuli. Users float in warm water saturated with a high concentration of magnesium sulfate, or Epsom salt, maintained at skin temperature (typically around 93.5°F). Since the water is shared, sanitation is a frequent concern for new users. Understanding the hygienic practices used requires examining the combined effect of the unique chemical makeup and the mechanical cleaning systems.
The Role of High Salinity in Hygiene
The fundamental defense against contamination in a float tank is the extremely high concentration of Epsom salt. The float solution is a hypertonic mixture, often 25% to 30% Epsom salt by weight, which is significantly higher than the fluid inside microbial cells. This extreme salinity creates an environment naturally hostile to most common bacteria, fungi, and viruses. The hypertonic pressure pulls water out of microorganisms through osmosis, inhibiting their growth and survival. However, the salt solution alone is not considered a sufficient disinfectant to rapidly neutralize all contaminants introduced by a user.
Active Cleaning Systems and Filtration
Float spas employ rigorous, multi-stage cleaning protocols beyond the passive effect of the salt. After every user session, the entire volume of water is cycled through a powerful filtration system. Industry standards recommend a minimum of three to four complete turnovers of the water volume between each float. The filtration process uses filters with extremely small pore sizes, often rated at one micron, capturing particulate matter far smaller than standard pool filters.
The filtered water is simultaneously treated with secondary sanitizers as it circulates. These treatments commonly include non-chemical methods like Ultraviolet (UV-C) light and Ozone injection. UV-C light destroys the DNA or RNA of microorganisms, preventing replication, while ozone is a strong oxidizer that breaks down organic contaminants. When UV and ozone are used together, they create an Advanced Oxidation Process, which is highly effective at sanitizing the water. Some facilities also use a small residual amount of a standard chemical sanitizer, such as hydrogen peroxide, to maintain water purity.
Primary Contamination Risks and Pathogens
Despite the multiple layers of sanitation, risks exist primarily due to failures in operational protocol. The main biological concern in a warm-water environment is the highly resistant bacterium Pseudomonas aeruginosa. This organism thrives in warm, moist areas and can potentially cause skin rashes or outer ear infections. The presence of Pseudomonas is almost always linked to inadequate operation of the active filtration and sanitization systems.
Contaminants, such as skin oils and personal care products, are primarily introduced by the user, making the pre-float shower an important procedural barrier. Furthermore, the high density and bitter taste of the salt water significantly lowers the risk of ingesting the solution compared to a swimming pool.
How to Evaluate a Float Spa’s Cleanliness
Prospective floaters can take several practical steps to gauge the cleanliness of a facility. The simplest check is the clarity and smell of the water; the solution should appear crystal clear and have no discernible chemical odor. A strong, unpleasant chemical smell may indicate an imbalance in chemical sanitizer levels.
You should inquire about the facility’s specific sanitation procedures. Ask the staff about the number of times the water is filtered between sessions, confirming they perform at least three to five full turnovers and utilize a combination of UV and ozone or an equivalent advanced system. Finally, inquire about their water testing schedule, particularly if they routinely test for Pseudomonas aeruginosa, which demonstrates adherence to best practices in public health monitoring.