How To Lower Alkalinity In Hot Tub Naturally. Common choices are liquid muriatic acid or dry sodium bisulfate. Proper alkalinity is an important part of hot tub safety.
If you need to increase the alkalinity, add total alkalinity increaser in the amount shown on the back of the bottle. Leave it for 20 minutes and turn off the spa. Also, you can try borax to raise your ph with little affect on the ta, so although borax does not lower ta, it won't raise it when trying to raise ph like other products will such as baking soda or soda ash.
The easiest way to lower hot tub water alkalinity is to simply add sodium bisulfate to the water.
For that add 30 gm, 1 capful of sun boom to the water. If the cya levels that are more than just a little high, diluting your pool water is the only way to lower them. Whenever you add chemicals to your hot tub water, you should turn on. Your hot tub’s water alkalinity is one of the most important steps in managing your water and keeping it safe to soak.