Pseudomonas is the equivalent of what is called “Hot Tub rash”. It is a bacterium that latches on to the hair follicle. It is common especially in new hot Tubs. The solution is cortisone applications and to run it’s course takes a week to ten days. It is caused by bacteria in the water. To confirm this you could ask your dealer bor a bateria test or seek a source where you can get one. Basically, it is a small petrie dish for testing a water sample. It will "grow" colonies with in 24 hours of the test.
With the high levels of bromine in your water, I would think you have enough sanitizer to kill bacteria. You MUST balance your pH and Alkalinity so they are in the OK range and test the water for “free” chlorine or bromine indicating an active sanitizer. Water chemistry is VERY important and should be treated seriously.
Once you get the hang of it, everything will fall into place. You are now in the advanced stages of learning about Hot Tubs.
Sensitivities and allergies are a possibility, but I would go the most common first. You water should sparkling clean and crystal clear before using the spa. If it is not, don’t use it until it is. I would recommend dumping the water and starting fresh and switch to granular chlorine and only granular crystals of chlorine. Not liquid, not tablets, but granular.
What kind of spa is it that you are working with and do you have an ozonator?
