Chlorine tabs or multi-function chlorinating granules [Archive]

chem geek

06-01-2013, 05:18 PM

Welcome to The PoolForum!

They are both problematic since both techniques add things you don't normally want increasing in your pool. The following are chemical facts that are independent of concentration of product or of pool size:

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

A multi-function product does not let you tune to add exactly what you need to the pool, but even the separate products of tabs, algaecide and shock are more than is necessary. "Shock" products are nothing more than chlorine sold at a higher price. There is nothing special about them and they could be used for regular chlorination except for the fact that they add either CYA (e.g. Dichlor or Trichlor granular) or CH (Cal-Hypo) to the water.

You can more readily manage your pool by using chlorinating liquid or bleach as your primary source of chlorine. The only other product you will need every now and then would be some Muriatic Acid to maintain pH. I only use 12.5% chlorinating liquid and a small amount of acid in my 16,000 gallon pool and these only cost me $18 per month, but I have a mostly opaque pool cover that keeps my chlorine usage down. Nevertheless, even if the pool were open, it would still only cost around $35-40 per month.

Tell us more about your pool -- is it indoors or outdoors? is it vinyl, fiberglass or plaster? how big is it? what kind of filter (sand, DE, cartridge)?

One of the first things you will need if you want to properly maintain your pool is a good test kit -- the Taylor K-2006 you can get from links in this post (http://www.poolforum.com/pf2/showthread.php?14994-How-to-Get-the-Right-Testkits-for-your-Pool).