Tested water with new TF-100 Kit

[weatherillgrp]

My kit arrived today.

My readings are as follows:

C- 3.0
PH - 7.2
CC - 2.5
CH - 275
TA - 170
CYA - 90

 

[weatherillgrp]

Since PH is 7.2 I presume I aerate the pool? The CYA is a high 90. Pool Math says replace 56% of the water. I changed 70% several weeks ago and I presume the CYA is high because I was using dissolved Trichloroethane then. I have now switched to 8.25% bleach. Even with a safety cover I have had trouble maintaining the Chlorine level. I now know that the CYA level is my problem. Anyway to get it down without replacing the water?

 

[timerguy]

unfortunately--nope. But__ why so low for a target? that's 27 ppm 44% will get you to 50 ppm

 

[duraleigh]

Yeah, I'm with timerguy...shoot for a CYA of 50 ppm which will be a 45% drain.....You'll never regret it once you do it and the savings on chlorine are immediate.

Your pH is fine...leave it alone

read "The ABC's of Pool Water Chemistry" up in Pool School. That'll refresh the basics and, importantly, give you acceptable ranges in which to operate (i.e. pH is fine at 7.2 - 7.8)

 

[weatherillgrp]

I am dumping about 12,000 gal. I will refill overnight. I presume I need to retest when I have it filled and bring FC to 3 and PH 7.4. I presume CC, TA and CYA should be in acceptable ranges?

 

[Isaac-1]

The target chlorine level for a CYA of 50 ppm is 6 ppm FC

Ike

http://www.troublefreepool.com/content/128-chlorine-cya-chart-slam-shock

 

[weatherillgrp]

Does that mean that you maintain 6ppm from then on? Also will that level of chlorine have any adverse effect on the vinyl liner? Thanks for the help. I'll get this soon. Learning every day.

 

[bridgman]

Take a look at Pool School => Handy Reference => Chlorine / CYA chart. For 50 ppm CYA the FC range is 4-6 ppm, so never let it get below 4ppm and each time you test bump it up to 6 or a bit higher.

Higher CYA levels moderate the effects of the chlorine, so all of the CYA/FC combinations in the chart have the same (mild) effect. Shouldn't bleach liner or have any other side effects.

 

[weatherillgrp]

I had to be gone for 10 days and my wife checked the Chlorine and PH daily. The pool took very little bleach and the PH maintained at 7.5 all the time I was gone. Prior to leaving the CYA was 30 and when I returned and did the weekly tests the CYA was 20. Is this normal? My 30 reading was just after I dumped and refilled 12,000 gal of water. Pool math says I need to add stabilizer to bring it up to 30. Would granulated trichloroethane work to do this? Water is pretty clear.