all parts pool and spa / Part Number 82-128-1025 ,
You don't have to go around with green hair looking like the Hulk! There is an answer! And it requires some simple, but diligent maintenance on your part.
It is especially important to have properly balanced water when a pool is heated with a copper or copper alloyed coiled heat exchanger. These are often found in gas pool heaters, but other heaters use them also, so you should always monitor your pH diligently when you have a heated pool. Though any time the pH is too high or low it causes problems for the equipment, too low pH causes the dreaded green hair and also ugly green finger nails.
Gas pool heaters commonly use big copper coils for heat exchangers. The water passes through these heated coils and takes some of the heat back to the pool. Over time this makes your pool toasty. Gas heaters are great because they warm the pool quickly and they can work even when it is very cold outside. But all pool heater coils are very sensitive when it comes to pH.
High pH in your pool water means the water is alkaline; this encourages calcium deposits in your heater, restricting flow and function. A low pH in your pool water means the water is acidic. Acids are great solvents, for example, think of stomach acid, it breaks down our food for us. Cola soda is acidic and it can dissolve a human tooth or strip the paint off of your car. It's also good for clearing out clogged drains!
Acidic pool water dissolves the pool fixtures, including the gas heater. When acidic water passes through the copper heating coils it takes away more than heat. The acidic water corrodes the metal, taking little bits of copper back to the pool. The small amount of copper in the water usually doesn't show up when you look at the pool until the problem is very bad. But, these little bits of copper in the water cause fingernails to turn green and hair acquires a lovely shade of green. Blondes are the worst affected, but brunettes and darker hair changes too, it's just harder to see. This green color can be extremely hard to remove, particularly from blond and dyed hair since the copper binds like hair dye to the hair. It will fade with time but not quick enough for most people.
To ensure you don't get angry, and nobody will like you when you get angry, make sure the pH in your pool stays between 7.2-7.8, with 7.5 being perfect. Testing your pH on a regular basis and adjusting your chemicals to keep the readings in the proper range is essential. That way, the copper in the heating coils will stay in the heating coils, and not end up on you or anyone using your pool!