I also have a hot tub and I use no bromine or chlorine.  I use a filter that you only need to replace twice a year, but for the life of me I can't remember what it's called now, but I'm sure there are more brands out there than just the one I have.  I do use the shock and pH balancer, haven't found a way to get out of that yet!!!  I just went in the store when I first got the tub and asked them for an alternative to the bromine and chlorine and they gave me this filter-type thingie that just sits on top of the regular filters.  It works really well.  In fact, now that I think about it, I'm two months overdue to get another one, and the water is still fine!!
   
  Love,
  Bren, who would go downstairs and see what the name of that filter is, but it's colder than crap down there right now, lol  :)
  


I have a spa, and I use no bromine, and only a rapid dispersal 
chlorine shock now and then - less than weekly. I use monopersulfate 
once daily in a low amount, and I run an ionic purifier of copper and 
silver in the filter. I think that if I had an ozone generator I 
could do with less than that. The chlorine and MPS are both 
completely oxidized and gone rapidly, before I contact the water. I 
can verify this with test strips.

This is a huge issue with me, as I filter and treat both shower and 
drinking water, too.

ginny


All stunts performed without a net!



 
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