Frank and Jacque discuss an issue with extremely high alkalinity and how to fix it. The ends and outs and myth-busting beliefs about alkalinity.
Credit to Ipssa “Basic Training Manual” and “Intermediate Training Manual” by the late, great Robert Lowery
00:00 Intro. What’s up with Frank and Jacque
05:40 Fellow Poolwerx franchisee Poolwerx Haslet is dealing with extremely high alkalinity and asked Frank’s opinion about the best way to lower it.
Alkalinity is the buffering capacity of water. It is the amount of carbonates, bicarbonates, hydroxides, and other things. It is very important in calculating LSI in a swimming pool. Some things will affect your alkalinity test results. CYA will falsely read as alkalinity. You should subtract 1/3 of your cya reading from your alkalinity test results. If you use borates, you can subtract 1 (one) ppm of alkalinity for every 10 ppm of borates in the water. Source water can be extremely high in alkalinity and create issues trying to keep water balanced.
11:45 To lower alkalinity, you use acid. Muriatic or sulphuric acid, or dry acid, which is sodium bisulfate. Acids lower alkalinity and pH. No matter how you add the acid, it lowers both. There are myths about how you can affect how acid lowers either pH or alkalinity by how you add the acid. But these are wrong. Acids will always lower pH and alkalinity at the same rate regardless of how you add them to the water.
Because of the effect on pH, you have to be careful and strategic when dosing acid to the water to lower alkalinity. You can easily violate the LSI and damage your pool surfaces and equipment.
Chemical products that raise pH (sodium carbonate, sodium bicarbonate) also raise alkalinity. This means we have to find a way to lower alkalinity and then adjust our pH back up without raising alkalinity again
The way to raise your pH without raising alkalinity is aeration. You can aerate your water by disturbing the surface of the pool waterfalls, aiming return jets at the surface, injecting air into the bottom of the pool, and spraying water across the surface are all ways to aerate the pool and increase pH.
The recommended way to adjust extremely high alkalinity to manageable levels is to do several small doses of acid over time, 10 to 20 ppm per dose, and aerate the water to prevent lowering pH to levels that damage your pool and equipment. Test before each dose and make sure you are not violating the LSI. Do not rush the process.
You can listen to “The Deep End Pool Podcast” every week at 9:00 AM CST on Saturdays. You can LISTEN LIVE online on TURF’S UP RADIO!
Do you have a pool question for Frank? You can email him at [email protected]. He just might read and answer your question on air!