It's close but not the same. What you picked up is 'generic' pH up (CarlD has talked about it's availability). Some of the real chemists here could probably tell you the exact difference (and, considering how long it takes me to type a post, probably have ) but what you have will give a big rise in pH and a small rise in alk (baking soda - sodium bicarbonate - will give a larger rise in alk and a smaller rise in pH). If both pH and alk are low, go ahead and use it, but you won't get the alkalinity increase that baking soda would give you and the pH will go up quite a bit. There's the whole 'carbonate alkalinity' thing that I kind-O-understand but not well enough to explain. Richard, Evan, Pat, Steven, Michael, et al could tell you, one of them will probably see this and expound.