Ask 'Dr. Spa' Q & A Message Board

Ihave tub rated at 250 gallons. I have been using 1 tsp chlorine after each use and weekly shock. I used my tub this afternoon, added 1 tsp and used it 10 hours later and checked with strips and it showed around 5 ppm. Using this method should I keep trying to use less, like 1/2 tsp or so, until 12 hours later it shows zero. Or should I wait 24 hours? I use this method because I have psoriasis and afraid of having too many chemicals in the water. Even when I use tub twice a day I still have been adding 1 tsp afterwards. Also, if not using tub for like 3 days, is it ok to not dose, or should one put like tsp in at least every 2 days if tub is not in use. Thanks