Just got a new spa a few days ago. I've done a bunch of reading and think I have a good handle on how everything interacts, as well as what's actually in all the magic products we got in the startup package. (Rather annoying that the vendors try to enforce lock-in by leaving ingredients off their products. Yay for mandatory datasheets. Anyway.
What I'm wondering is, when we have people over on a warm, sunny day, we'll want to leave the spa open so that people can get in and out as they like, as well as just for the ambiance. However, I've definitely noticed that the bromine level drops pretty quickly with the cover off in direct sunlight. What's the best way to ensure that the level doesn't drop to zero while it's out in the sun? We got SpaGuard products with setup, so there's a "brominating concentrate", which I guess is sodium bromide plus some dichlor, brominating tablets (same deal in tablet form), and "Spa Lite", which is a DiChlor shock in weekly dose packets. (Plus an "optimizer" (adds borates) and cleaners and such.)
My guess would be to just add a bit of DiChlor when it's first opened - not shock level, but just a bit to bring the bromide levels up to 5-6 or so, and perhaps again after a few hours if levels are low? Would a non-chlorine shock or something else be more convenient for this?
We're also having an ozone system added soon (was included in purchase but not in stock), which presumably will help somewhat, although I doubt it will be able to keep up with the amount lost to sunlight on its own.
We have a SWG for our pool and it really is almost maintenance free. Would be great to get to a similar place with the spa. (One of the reasons I went with bromine was my understanding that they could be lower maintenance than chlorine with an ozonator and the tablets.. but I didn't realize how fast the sun would eliminate it. Maybe chlorine with a SWG would be a better option?)