Dead Sea Salt Natural Hot tub

[skratt]

Hi

 I am buying a wood-fired hot tub with a fibreglass liner. Not jets, no pump. Just a marine grade stainless steel stove that will take the salt water abuse. 

 It's for a eco lodge in the tranquil hills of Wales. UK

 We have guests staying for between 3 and 10 days and plan to change the water in the tub for each set of guests. 

 We don't use any chemicals in the whole lodge, nothing.  So it would be great if there was a way to keep the hot tub water chemical free and natural. 

 I can get dead sea salts and epsom salts in bulk from a cheap source if that helps. 

Is there a way ?   Thank you in advance. 

ps.  no over complicated scientific answers please.  Those that feel the need to sound clever clutter my simple peasant brain.  

[Dr. Spa]

If you don't use something to sanitize the water most likely your guest will get sick, sue, and cause you to go out of business. There's noting other than chemicals to sanitize the water.

[arobbert]

You could use something like a Saltron Mini-II Spa Salt System Chlorine Generator (below is a link). They are often referred to as a salt water system though they generate chlorine. You can refer to it as a salt water system to your customers. It will provide reasonable sanitation if set up properly. You need to be careful because you are in a commercial application. This greatly increases the need for proper sanitation to avoid problems compared to an individual user at home. The amount of sanitation needed is affected by the number of people, frequency of use and how well people bath before entering. Think of multiple people taking a bath together and not changing the water.

http://www.spadepot.com/Saltron-Mini-II-Spa-Salt-System-Chlorine-Generator-P10105C43.aspx?zmam=55673001&zmas=1&zmac=1&zmap=CX1004&gclid=Cj0KEQiAzNfDBRD2xKrO4pSnnOkBEiQAbzzeQTPG8iiQbJysR6uYFf_XhXl2mb7LJpZ5HhuUPJwR32caAtsO8P8HAQ