Minimum Pool Maintenance This Year! Why?

[chem geek]

That's a good question for which I don't have a good answer. Sodium hydroxide (aka lye or caustic soda) is a pure base and a compliment to Muriatic Acid. It shouldn't be any more dangerous and in fact is mostly what crystal Drano is composed of (though that product is not pure enough nor granular enough to be used in pools). Sodium hydroxide would work best in pools that use Trichlor, but don't get a lot of carbon dioxide outgassing, such as those with pool covers that are on most of the time.

[ItsAllInTheNumbers]

Trichlor tabs contain 90% availabale chlorine, leaving only 10% for CYA and other additives.

Ummm not quite. Let's look at the chemical structure of trichlor, it's basically a cya ring with 3 chlorine molecules attached to it.

Let's find the molecular weight of trichlor (it's 235 g/mol), the chlorine molecules (it's 106 g/mol) and the cya alone (it's 129 g/mol).

106 ÷ 235 is 45%
therefore 45% of trichlor by weight is chlorine. You have to multiply that figure by 2 (for reasons I won't get into here), so trichlor yields 90% available chlorine (when compared to chlorine gas).

129 ÷ 235 is 55%
therefore 55% of trichlor by weight is cya.

[Allen G Myerson]

232.41 grams of trichlor contains 212.718 grams of Cl2 equivalent, but only 106.359 actual grams of chlorine. The chlorine only makes up about 45.76 % of the trichlor. About 54 % of the trichlor is cyanuric acid.

[joansy1]

I have used a product called Pool Line-Away and it quickly removes the calcium line from the tiles. Just put the wheel in a portable drill and off the calcium goes. :