Our water heater is small so we turned it up to the hottest setting to get the maximum amount of hot water. We found that the highest setting was too hot for the plastic, so we added quite a bit of cold water. Next time we will not set the heater so high and thus need less cold water. The temperature stayed between 100 degrees and 97 degrees for about an hour. By then our heater was hot again and we could add extra water. I think we are in business!
It was so nice to be in the tub. The bottom of the tub is inflated with air so I wasn't sitting in the hard floor. The sides are really sturdy and handle my weight when I lean on them. However, the whole tub rocks a bit when I lean on the sides. The walls are thick, I feel confident about their sturdiness, but it made me pause a little the first time I felt it. I would hate to spill all that water!
After I relaxed in the warm water for awhile (bathtubs just aren't comfortable anymore!), I invited North to join me. He also liked the bouncy floor. In the picture he is holding the floating thermometer. We practiced putting our faces in the water and kicking our feet. I see great potential for a summer swimming pool.