Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 3 of 3

Thread: New Pool Owner - question about TF-100 CYA R-7065 standard

  1. Back To Top    #1
    sddiver's Avatar
    Join Date
    Mar 2016
    Oceanside, Ca

    New Pool Owner - question about TF-100 CYA R-7065 standard

    Hello all,

    I'm thrilled to finally make my first post to what has been a wonderful resource for me for months!

    While I had great plans to fully document our pool build in Oceanside CA on TFP all along the way - somehow that did not happen and the build was completed last month, but I will post some pics anyway of various stages in another thread.

    I found TFP well into the process - and was immediately sold on the methodology embraced here. Although the build process went really well I would have done a few things differently if I had learned more earlier in the process. No regrets, happy with the end result and where we are now, just would have done a couple things differently from the start (I will post those in a different thread and speak to the PB interactions to hopefully help those at the start of the process).

    First I just want to say thank you to all the folks that take the time to post and respond sharing information and knowledge - this is so valuable to us lurkers who are trying to learn about the process and the myriad of decisions along the way to building and spec'ing a new pool.

    Sorry for the long intro - now on to my question:

    > like many newbies I had some trouble interpreting the CYA results. Since I had the TF100 kit, it comes with a 50PPM +/-5 R-7065 standard to train one at reading the results. When I use this material (performed test twice with same results), the dot does not disappear until around 25PPM (see photos). I attached 2 photos, 1 showing the vial filled to the 50PPM line and another showing the appearance of the dot with the camera held at eye level and the vial at waist level at 50PPM. Am I doing something wrong or is there possibly something wrong with the 7065? My own pool water shows a CYA of around 60 with the dot totally gone and 70 with it gone-ish. Since i recently switched from the PB installed Fusion2 to a SWG I am trying to get my CYA to SWG levels (70-80). I have not added any CYA yet, the level it is at is from only the PB pool service trichlor tabs they used for the first month (1 pail - about 8lbs). My most recent test results are below:

    pH - 7.3 (I did this on purpose this morning to reduce TA - will raise with aeration, was at 7.6 B4 I added more acid to get to 7.2 per pool math)
    TA - 90 (still trying to get this down to 60 before going to Borate in the future, was at 100)
    CH - 275
    CYA - 60 (or 70 depending on how gone the black dot is supposed to be)
    Salt - 3400

    Thank you for any input,

    18500G Freeform IG pool & spa. 39'x19' Wet Edge Satin Matrix Tahitian Tropical. AquaPure 1400 SWG, JXI 400K BTU HTR, VSSHP270AUT 2.7HP VS PMP, 460CF + CS150 Cart Filter, PFPF2.0 2HP jet pump for spa jets, 1HP wtr ftr pmp Jandy LED RGBW 9W Nichless lights (3x-pool, 1x-spa), 2 - 24" sheer descents, 4 - deck jets, 2 - LED Laminar jets, Construction start 5/5/16 - Fill date 8/9/16. SD County SoCal (Oceanside). TF100 test kit

  2. Back To Top    #2
    harleysilo's Avatar
    Join Date
    Mar 2012
    North Georgia

    Re: New Pool Owner - question about TF-100 CYA R-7065 standard

    Sounds like you got it Goin on. Pool math will calculate what the 8 lbs of tri would have raised your CYA, you can use that as a sanity check. Not sure why the standard solution didn't show 50.
    18'x43' Sport Pool
    19,000 Gallons Vinyl Liner 3'-3.5'-4'
    SWCG and D.E. Filter
    Test Kits - Pool Calculator - Chlorine/CYA Chart - Pool School

    Secret Weapon for Pool Chemistry Testing

  3. Back To Top    #3
    Mod Squad
    Join Date
    Aug 2012
    DFW, TX

    Re: New Pool Owner - question about TF-100 CYA R-7065 standard

    Welcome to TFP!

    Do the test with your back to the sun. Let as much light into the side of the tube as possible. Hold the tube at the top with a finger and thumb. Pour it back and forth as often as you want to try different lighting. Many folks find that the test reads around 40, some folks say 50. Always round up your CYA to the next 10, it is only 1 more ppm of FC. And remember it is safe to swim with FC above minimum and up to shock level. There is a lot more room between target and shock level then there is between target and min.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts