Trying to Learn!!

[cindyslou]

I have been trying really hard to actually understand all about the testing of our pool. My current test results are:

FC 17
CC 0
TC 17
TA 110
CH 280
CYA 95
PH 7.5 - 7.8

Parts of our pool walls feel slick - not all of them. The water looks clear. What am I doing wrong? I have read & read this forum for hours & feel as though I have learned a lot but then I still feel like a dummy! What am I doing wrong? Thanks for the help!!

 

[Suziqzer]

Sometimes people think vinyl liners feel slick, sometimes it's algae.

Have you done an overnight chlorine loss test? That should tell you if it's algae, or just the way the liner feels to you.

 

[cindyslou]

Our pool is plaster, but I haven't done the overnight test. Is it done differently from a regular chlorine test?

 

[jblizzle]

Well, if the walls are slick, that is likely algae and you need to go through the Shocking Your Pool process. Some other reading with more info: Defeating Algae
and
Turning Your Green Swamp Back into a Sparkling Oasis

Note that your CYA is pretty high and a 50% drain/refill would help tremendously. For a CYA of 95, the FC shock level you must maintain is 37ppm according to the Chlorine CYA Chart.

While at shock level, brush all the walls very well to help remove the algae.

The previous post does give a good recommendation to try the Overnight FC Loss Test to see if there is something living in the pool.

 

[RobbieH]

Using an SWG, a CYA level of 80 isn't unusual. If it were me, I'd make absolutely sure I had an algae problem before draining water.

 

[jblizzle]

Using an SWG, a CYA level of 80 isn't unusual.

OOPS ... missed the SWG in the signature. CYA of 95ppm is still a little high. In either case, the FC require shock value is above 30ppm ... if you confirm the presence of algae from the OCLT.

 

[RobbieH]

The good news is draining part of a pool that size isn't a huge volume of water to get CYA down into the 70-80 range. 4,000 gallons should get you pretty close, just 25% of the pool.

 

[cindyslou]

Thanks all! Will do overnight test & post results tomorrow!

 

[cindyslou]

Okay did the OCLT and chlorine is at 18. We turned the SWG down to 35% to see if that will lower chlorine level. TA 110
CH 280
CYA 95
PH 7.9

Any suggestions on my slick walls? Really want to get a good grip on all of this! Thanks!!!!

 

[jblizzle]

Sounds like you need to review the instructions on how to do the OCLT. I know there is a link in the shocking your pool article in pool school.

EDIT: Here is the link: Overnight FC Loss Test

 

[cindyslou]

I turned SWG off, about an hour later, 9:00, did test got 17.5, this morning at 7 & got 18. Did I do it right? Also, do I need to continue with this post or start a new one?

 

[jblizzle]

OK, well sounds like you did it correctly, you did not mention the night test in your previous post. That said, the FC should not have gone up ... that is not possible if the SWG was off ... maybe the pool was not fully mixed for the night test. Was the pump on all night? I would suggest trying the OCLT again, although seems like you should be fine. How does the water look?

Really before continuing, you should decide if you are going to drain some of your pool to get the CYA down a bit. And then get all the levels straightened out.

And keep all your posts here for continuity.

 

[cindyslou]

Thanks Jason!!! The pump did not run all night. I will let the pump run tonight & repeat the OCLT again. Will post results in am. Thank you so much!!!