My husband and I bought a used hot tub a few weeks ago. I'm estimating the tub to be approx. 320 gallons. I've read through how to chlorinate your spa several times but I'm finding myself much more confused about maintaining it than our pool.... To begin we superchlorinated and ran ahh-some. Or fresh fill results were FC 0, PH 7.6, CH 0, TA 100. I added calcium, cya (target 20 ppm), acid, and chlorine. I managed to get the TA down to 60, and CH to 100 ( will add a bit more calcium to raise a bit higher). I brought the FC to 12 ppm and by evening it had dropped to 4 ppm. My husband was anxious to try it out, so we enjoyed our first soak, approx. 1 hour. I tested again right after our soak and FC was down to 2, so I added enough chlorine to bring back to 6. However, today our FC was already down to 1.5 prior to anyone soaking. I was nervous that if it was only 1.5 prior, that we would drive it down to zero during our soak (4 young boys, 2 adults) so I added enough chlorine to bring FC to 6 prior to the soak. Once we were done FC was 4 and then 3 hours later was down to 2.
So my main questions are:
-when do you normally test your tub? Before and/or after soaks? (Our boys will most likely be going in and out of pool/hot tub several times during day, I would like to be testing once a day at the most)
-is my FC dropping too quickly? Or is this expected? (I don't believe we have an ozonator)
-should my chlorine target after soaks be higher than 6ppm?
-if my boys are going in/out of tub several times during the day, do I need to be adding chlorine after each soak?