Just had a birthday party for my 7 year old. We had about a dozen 7-year-olds in and out of the hot tub and between the hot tub and the pool for the last 2 hours.
I changed the water in the tub 2 weeks ago and installed a new filter at that time. Started off with Brom Bank that I shocked appropriately. Since then the bromine level has been kept up in the 6-10 region by floater with bromine tabs. I balanced everything this morning and cleaned the filter
- Bromine about 10 (in anticipation of bather load),
- Combined Bromine about 4 (not sure why),
- TA 70,
- CH was 50, but I added enough calcium to take it to 110.
- PH 7.5,
- borates about 20.
After about 90 minutes of kids in the hot tub, I tested the bromine and it was down to about 1, so I kicked all the kids out and added 1/3 cup of 10% chlorinating liquid. After that, I noticed the hot tub take on a green hue. I hit it with some more chlorinating liquid, and it just got worse.
I'm thinking one of the kids had some icing on them and that it's icing that is dyeing the water green.
Any other reasonable explanation?