Toxic smelling fumes from spa

[MarthaCyr]

We've had our outdoor spa for about one year. In the past month it has vapors coming from it that immediately induce coughing.

Today my real water quality kit (vs strips) arrived and here is what I found:
TA 90 ppm
Calcium 500 ppm
Bromine 1 ppm
pH greater than 8

Guidance on how to make the spa usable again would be much appreciated!

 

[JoyfulNoise]

How often do you change the water?

 

[MarthaCyr]

The water hasn't been changed since the original fill.

 

[JoyfulNoise]

Generally speaking, hot tubs need to have their water changed a few times per year, figure about 4 changes per year. Bather loads in hot tubs are much higher than in pools because tub volumes are so much lower. Over time, the tub is building up bather waste some of which is oxidized by the bromine into volatile organic compounds but some fraction is converted into THMs (trihalomethane) which can persist in the water for a long time. THMs can easily cause the sick feeling you are describing. Also, your sanitizer level is far too low which could easily allow bacterial growth in the water and formation of biofilms in the plumbing.

I suggest you purchase a hot tub cleaning product called Ahh-some and use that to purge your hot tub. After the hot tub plumbing is purged, drain the tub and refill it with fresh water. Sanitize appropriately. Also suggest you use a supplemental oxidation system such as a UV light sterilizer (if available for your tub) OR you use a regular treatment of MPS to help destroy bather waste.

 

[MarthaCyr]

Thank you for the guidance. I replaced the water after using a cleaner to purge/clean the system. In the process I learned that ther is an ozone system attached to, but not active, in the system. Got the levels up to a basic level and then left for a 9 day vacation.

Home now and need to learn how to get the MCD-50 Del Ozone system working.