Salt water

[Susanj]

Does anyone here have a saltwater system hot tub or pool? I just came back from a vacation rental in Florida and didn’t get an answer from the host when I asked if that’s what it was .  When I licked my lips I could taste salt and I wondered if it was just sweating in the humidity (I’m from Denver), but then we realized it hardly smelled like chlorine at all- just very faintly.
It made me think I might want to switch our hot tub over,  but is it difficult with a vacation rental when you don’t live in that city to maintain it? ( We’ve had lots of difficulty finding competent service people for a bromine/chlorine system which is much more common). From what I understand,  you buy a unit ($600?) and when you add salt to it , it creates chlorine?

[ratchett]

I have a saltwater pool sitting next to my 2019 Hotspring Highlife Jetsetter which is compatible with the latest next-gen salt cell technology from Watkins/Hotspring.

In pools they work great - low maintenance.  Long story short, a bit of salt in the water gets zapped with electricity to break the sodium chloride down and releases free chlorine into the water.  This helps us use less chemicals to maintain the pool water.   However there are some issues - after only five years, multiple metal components have already started showing rust spots - handrails for the tub, drain valve tap is completely rusted shut (we now use a siphon setup to drain the pool which works faster but more of a PITA). Additionally the salt cell for my pool is crazy expensive - just under $2000 these days! 

On 6/6/2022 at 11:43 AM, Susanj said:

From what I understand,  you buy a unit ($600?) and when you add salt to it , it creates chlorine?

In theory, yes it sounds so simple. However in hot tubs the story is a bit different.  Your water must be extremely soft for the salt cell to operate properly.  If you have well water or hard water from the tap, you're going to need a portable water softener unit every time you refill the tub.   Luckily saltwater hot tubs can go longer months between water changes if you maintain the water properly (with my hotspring they advertise water changes every 12 months).

Which leads me to my next point - salt water systems in hot tubs require the water chemistry to be within certain ranges in order for the system to generate adequate free chlorine to keep the water sanitized.  You should be testing twice a month to ensure the system is generating adequate chlorine to keep the water sanitized.

Finally the biggest "problem" with saltwater systems is the fact that phosphates are REALLY bad for the salt cell electrodes. I've seen it happen so many times - people get a saltwater tub then start complaining because the salt cell is burning out four times faster than it should, only to learn that their water's phosphate levels are sky high.   Phosphates come from a variety of sources - lotions/moisturizers on skin, fertilizer on grass, soapy suds in bathing suits from detergents, etc) - when levels get too high, the phosphates must be sequestered from the water or the tub needs to be drained/refilled.   That would be a concern I'd have with random guests using a saltwater setup.