You will find Pseudomonas aeruginosa in almost any stagnet water. The problem in pools and hot tubs it rises to infectious levels due to bather use and warmer temps. If I rember correctly Pseudomonas aeruginosa is a nitrate lover so you may want a nitrate level checked. If the rash is a true Pseudomonas aeruginosa infection you NEED to see a MD. Folliculitis can become life threating quickly if the person scratches it. The worst thing you can do for a person in the hospital is take them flowers due to Pseudomonas aeruginosa in the water. We no longer allow flowers where I work.