For the past year or so, my 1999 Hot Springs Prodigy has been leaking. At worst, it drops an inch or more per week. An application of FixALeak stops the leakage for a couple of weeks, then it starts up again slowly.
My dealer couldn't find a leak, although he did recommend I change in spa light fixture and gasket in case that was the problem. Did it, but it made no difference. There is no obvious water in the motor compartment.
In the heat of summer, I don't normally use the spa. I just turn it down as far as it goes - 80°. That keeps the circulating pump going for filtering. I'd like to just disable the heater completely, but I can't see how to do that. This summer I thought of a way to get some benefit from the spa. I just drained it (regular maintenance) and filled it with cold water. Great for soaking. I flip the breaker to keep it from going back up to 80°. Then twice a week, I turn it for one 15-minute clean cycle, adding chlorine each time.
So here's the oddity where "part-time" comes into my subject line. Since I've been doing this, there doesn't seem to be any leakage. I have not put in any more fixaleak in quite a while. Given these facts, any idea what could cause a leak only when the tub is turned on, even without running the jets more than for two clean cycles per week?