Jump to content

How To Reduce Free Chlorine Level


Recommended Posts

Newbie here on the forum and to pools. We have a new above ground 21' diameter pool (10,600 gals) and went to the free pool school at Watson's. I understand that the free and total chlorine should be the same. If the total is more than the free, there is dead chlorine and a shocking will be needed. For the past few days, my free and total chlorine have both been between 5 and 10 on my test strip. I have had the inline chlorinator turned down to 0 for the past few days. We have a solar cover on whenever the pool is not in use (water temp reads about 82 F). The cya acid level reads about 10. Ph is a little low around the 6.8 mark. Isn't the chlorine supposed to evaporate? I thought that the issue would be not enough free chlorine but is seems I have too much. Any ideas what to do?

Thanks - Mike

Link to comment
Share on other sites

Mike,

Instead of using test strips for measurements, get a better test kit instead, the Taylor K-2006 you can get at a good online price here or the TF100 test kit from tftestkits.com here with the latter kit having 36% more volume of reagents so is comparably priced "per test".

Your CYA level should be higher, but I wouldn't trust the test strip reading. Did you just recently fill your pool with water and not add any Cyanuric Acid to it upon startup? That would explain a low reading. If you've been using Trichlor pucks/tabs in the inline chlorinator for a while, then the CYA level is probably higher since for every 10 ppm FC added by Trichlor, it also increases CYA by 6 ppm.

Chlorine doesn't evaporate (at least not quickly in pools with CYA), but it does break down in sunlight and does so quickly if you don't have enough CYA in the water.

Your pH is probably low because Trichlor is very acidic. You should probably add pH Up (Arm & Hammer Washing Soda; sodium carbonate) unless your Total Alkalinity (TA) is high. pH Up raises both pH and TA.

For more info on how to manage your pool, read the items in the Pool School.

Richard

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...