My skin always feels really itchy after using my personal hot tub. But when using a public hot tub at a hotel etc it doesn't?

So they say chlorine and bromine can be the culprit of why your skin feels itchy and I ended up switching from chlorine to bromine because it's a little easier on the skin and it maintains its levels better at higher temperatures versus chlorine.

But every time I get into my personal Spa I'll get out and my skin just feels really dry and itchy.

If I use a public hot tub or pool I don't seem to have that issue.

I use the Taylor testing kit with the drops as that provides me more accurate results instead of having to second guess on the color for the strips and I always have the bromine within range and it's not too high. The pH is within range too.

Using my personal Spa I can be in there for hours but sometimes even then I could just be in there for a half hour and I still can I get the same thing where my skin feels dry and itchy or like I can get into like a hot shower and it feels so good to burn the itch away.

But also I've been in public pools or Spas for long time to and I don't seem to face this issue.

Why is this happening?