Bromine smell and shock.

[qbquixote]

Lurking and hopefully learning on this forum for six weeks and am puzzled about what to do next balancing water.  Studied the excellent waterbear posts about a week after starting up the tub, using 3 step bromine.

Tub has over the last 3 weeks developed an irritating spa smell and fizziness with high jets despite my lowering my bromine target to 2 ppm after it started to develop.  

Installed a small marquis tub v65L 210 gallons 6 weeks ago.  Crystal clear water since installation daily testing except two short vacations.

Spa is used daily for about 1 person/hour

I use test strips as a multi factor screening and an ITS photometer test kit for more precisely following bromine daily with once a week and as needed pH (always 7.5-7.8) , and alkilinity tests (running 80-85). occasionally calcium hardness test.  I figured I would overtest to get the hang of this at first.

For most of the six weeks I ran about 5ppm bromine, but the last couple weeks reduced that targeting about 2 after the smell started to develop and I was concerned about running bromine too high given the ozonator and reading Marquis recommendations. Using the spa frog delivery of bromine, mineral cartridge and using MPS shock every 1-2 weeks.

Each MPS shock 2 OZ takes the bromine over 17 (limit of my test kit) and takes 2-3 days to come back down below 5. I leave the tub open after the shock (otherwise closed) and have to dilute for evaporation with hard water with some magnesium and Calcium - Calcium hardness about 300. I sometimes hop in when it gets below 8 to hurry bromine down and shower afterwards.

One usage of anti foam, and gentle spa.  Float 2 scum bugs.  (that really seemed to decrease some slight foaming at about one month in).

Most recent Tests

Bromine 1.5 ppm (this week dropped to zero once after use and did MPS mini - shock to bring back up to 2ppm)

ph -7.8 (7.5 3 days ago)

Alk- 83 (85 3 days ago)

So do I have an over-brominated tub with too many bromamines as well, but no unsanitized organics.  That's part of why I lowered my bromine target but its not helping.

I think I need to shock more because what I am smelling are bromamines which have built up without being shocked away.   Do I need to add alkilinity up to closer to 100?

Bromine takes a loooong time to come down after my shocks - which suggests I have plenty of bromine and not a lot of organics to sanitize.   I think I should not have old water at 6 weeks.

Not sure what to do next but the water is getting more irritating.

Thanks in advance for any ideas.