Testing CYA and sanitizing my spa with Dichlor OR Unscented Bleach?

[Nymike]

Hi, I'm a new spa owner. I have a decent background in HS and College chem, so I'm comfortable using the reagent test kits. I am using a Taylor K-2006C. My SI currently is 0.1 which I'm happy with. I like to run my tub on the cooler side as here in Vegas it's been incredibly hot...so I keep it in the 86-96 degree range if overnight temps permit. As of tonight my TA is 80, CH 275, pH 7.6, FC 0.2, Temp 96F.

My question is when testing CYA do you measure the level when the black dot in the comparator FIRST disappears as I'm pouring the sample in, or when the sample is fully settledand the dot is PERMANENTLY hidden?

If it's the former my CYA is around 80, if it's the latter then the CYA is around 35-40.
Either way I don't want to keep adding Dichlor. The spa was only filled 9 days ago and used 2x. I also installed in the filter a Nature2 mineral sanitizing stick so I don't need to add as much Dichlor.
Should I switch to plain Chlorine bleach as I've read elsewhere to keep the CYA from increasing?

Thanks!

P.S.
I will be getting a water softener in the next 8 weeks so my next fill will have a different CH.

 

[pooldv]

Welcome to TFP!

It is easiest to keep track of how much CYA you add by using Poolmath. Here are some reference pics of the CYA test, https://www.taylortechnologies.com/ChemistryTopicsCM.ASP?ContentID=36

Here is a great process for maintaining a hot tub with chlorine, aka dichlor then bleach process. I've been using it for years. How do I use Chlorine in my Spa (or pool)?

 

[Nymike]

Thanks for the info and links. In regards to the testing process can you clarify for me if I need to measure the level when the dot first disappears or when the sample is settled? Also, I tested mine in my kitchen under a soft white lightbulb, and I seem to understand now it should be done in the shade of my body, with sunlight at my back?

 

[Nymike]

Anyone?