You didn't specify the construction material of the pool and spa but let us assume you are talking about a plaster pool and an acrylic spa. With plaster you will aready have a buffer system going from the dissolving plaster and the acid used during startup and curing. With an acrylic spa it is all dependant on your fill water. As far as the amounts needed a given amount of sodium bicabonate will add a given amount of alkalinity to a given volume of water whether it is a pool, spa, or your bathtub! Unless the pH is WAY out of whack it is better to adjust the alkalinity first which will make it easier to maintain a given pH. I might be new at owning a pool but I have owned hot tubs and spas for many years. The biggest difference is in the amount of water so you have MUCH less room for error if you add too much.
A difference of as little as a teaspoon can be the difference of a properly balanced spa and one that is out of whack! Also the high water temperature and constant airation can also have a big negative impact on your alkalinity while possibly causing a rise in pH with such a small volume of water. In short, the larger the volume of water, the more forgiving it is.
Reply With Quote
Bookmarks