I found an old invoice from when our hot tub was new 4 years ago (and I didn’t understand anything about it back then ) . The service person -a hot tub company - had detailed everything done on the invoice.
He had written that water was green before he treated it , bromine was 15 (!) and he got it to 6 and used this product to do that. I have no idea why it would’ve been 15 because he had serviced it before guests came to our vacation rental and it was only three people there for two nights . Though I think he waited five days to come out after they left. Or maybe because it looked so bad he gave it a super dose of shock and got the level up way too high ( intentionally?) so then had to get it down? We didn’t keep that company long.
I asked the question because I thought we might need to use it someday in the event that we inadvertently get bromine over 10 with shock and are having people coming in the same day. Leaving jet’s running & the cover open for a few hours , I don’t know if it would get it down enough , and I would hate to do that anyway with the property unattended.