5 is the highest that the kit can read. Are you sure it is 5 or is it darker yellow? Did you look at the link I posted above with the color chart?

To try and clear the pool, you need to maintaining chlorine levels around 15ppm. Does the Blue Shield Liquid chlorine mention anything else on the ingredients? If not, it is probably fine to use.

In your pool, each cup of the 12.5% sodium hypo will add about 1.5ppm and each quart will add just under 6ppm. Use that as a reference to help you figure out how much to add each time you test to get the chlorine back up to 15ppm. However ---- it may be that it is not actually 12.5%. Chlorine degrades quickly. Who knows how fresh that is. That is one reason we like Walmart's generic bleach. It is stored in an air-conditioned store and the turnover of the product is quick. I just left my Walmart a few minutes ago and bought several jugs myself!

You really should think about order the K2006 kit I mentioned above. It can measure chlorine levels higher than 5ppm.

Another chart you should look at explains the connection between CYA and chlorine:> http://pool9.net/cl-cya/ Not understanding this connection is one of the main reasons that people get algae in their pool.

Basically, you want to keep your chlorine high until you can go from sundown one evening to within an hour of sunrise the next morning without losing more than 1ppm of chlorine and the water is clear.

Don't worry about the hardness right now. Also, when you test, you don't need to retest the CYA anymore unless you use a product that has it in it like dichlor or trichlor. And, you shouldn't use either of those. Your CYA is perfect right at 50.

One more tip for now, the pH results will be invalid with your kit when the chlorine is over 5ppm. (Over 10ppm with the Taylor K2006 kit.) So, if you have high chlorine, dilute your water sample before testing pH. Take one part pool water and mix it with an equal part of distilled water. Then, run the pH test with that as normal.

Hope this helps. Let us know if you have further questions.

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