Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 8 of 8

Thread: Does it matter where you take your water sample from?

  1. Back To Top    #1

    Join Date
    Jul 2015
    Location
    San Marcos, CA
    Posts
    110

    Does it matter where you take your water sample from?

    I've plumbed a faucet into the backflush valve housing which allows me to take a water sample at the pump (when the pump is running) instead of crouching down at the pool. It's a convenience thing and easy on my back and knees.

    I can't see why it would matter, but since I've never posed the question I might as well ask the brain trust: Is there any reason to suspect this isn't a good approach?
    16 x 32 IG plaster pool, 23k gallons, built 1992, DE filter, Pentair VS pump, IoThyngs controller, Taylor 2006 test kit, SoCal water restrictions
    Newbies with green pools, see SLAM and Recommended Test Kits. My company: IoThyngs

  2. Back To Top    #2
    borjis's Avatar
    Join Date
    Aug 2014
    Location
    Pacific NW
    Posts
    2,055

    Re: Does it matter where you take your water sample from?

    I'm not sure exactly if it is, but I do know it is mentioned often here to get your sample, from "1 foot below in the deep end."

    so thats what I do.
    16x32 IG Vinyl, 13,000 Gals. Hayward S-244T sand filter, SP2810X15 pump
    (1.5 HP motor) Raypak PR266AEN (266k btu) gas heater. TF-100 Test Kit.
    Dolphin E10 Cleaning Robot.

  3. Back To Top    #3
    Mod Squad YippeeSkippy's Avatar
    Join Date
    Jan 2012
    Location
    'burbs of Augusta, Georgia
    Posts
    6,479

    Re: Does it matter where you take your water sample from?

    Regarding the OPs desire to save wear and tear on their knees and back- try using a piece of narrow PVC pipe (maybe 3' long or so) as a pipette to withdraw water from deeper down in the pool without bending over. Works a charm!
    My Amazon Smile for November12K Fiberglass IG, Infinity 4000 automatic cover, SWCG, Hayward Sand Filter, Hayward 1.5 Pump, Doheny Discovery Robot, Savi Melody LED pool lights, outdoor speakers and other assorted doo-dads. Sundance Altamar Hot Tub.
    Our pool build--> Our Pool Solved Our Sloping Yard Skippy's Cheap Pool Cooler -->Skippy's New Fountain

  4. Back To Top    #4
    Mod Squad tim5055's Avatar
    Join Date
    May 2014
    Location
    Columbia, SC
    Posts
    8,495

    Re: Does it matter where you take your water sample from?

    Just let the faucet run for a moment before you take the sample so any "dead" water that may be trapped in the faucet does not become the sample.

    Now, this would not be a good idea if you have any chemical automation that may inject any chemical just before the faucet.
    TFP Moderator 39 X 18 23,000(ish) freeform gunite; built 2007ish; Pentair Triton II TR100 600lb Sand filter; 2 HP Pentair pump with 2.2 HP AO Smith single speed motor; 2 skimmers, 1 main drain, 4 returns w/waterfall, Stenner 45MHP2 3GPD running@ 60% - 15 gal Tank; heated by the sun CYA 200+ when I started - 50 now. Dolphin Supreme M5 Pool Cleaner. Hot Springs SX Spa, 285 gallon

  5. Back To Top    #5
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,591

    Re: Does it matter where you take your water sample from?

    It does to the extent that you want to get a sample of water from the bulk of the pool, not near the wall, not near a return and certainly below the surface by at least a foot.

    My only concern with using the spigot at the equipment pad (I have one to right after the pump but before the filter), is that you can't be sure of the water sample you are getting. If the pump is drawing from the skimmer mainly, then that water is mostly surface water from the pool which could be low in FC due to sunlight degradation. If there are main drains involved, then that's a little better because the water is coming from both deep in the pool and at the surface but it would be hard to know what the proportions are. Obviously getting a sample from the deep end using a long draw tube like a straw (with your thumb initially held over the opening) lets you draw a deep water sample. But I also empathize with your back and knees as I have had past back issues and it is not fun at all.

    So, you could try to take two samples of water, one from the pool and one from the spigot, and see if you can detect any differences. The biggest difference should be in the FC level as surface water will be depleted of FC from the sun. I would expect the pH to be fairly uniform. The TA might be noticeably different at the surface.

    I'd be interested to see how your experiment turns out....good luck.
    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

  6. Back To Top    #6

    Join Date
    Jul 2015
    Location
    Western NC
    Posts
    115

    Re: Does it matter where you take your water sample from?

    Taylor Technologies suggest "To get a representative sample, draw the water from mid-pool"

    http://www.taylortechnologies.com/Ch...P?ContentID=69
    23,000 gallons IG gunite, pebble (I think)
    Hayward SP2610X15 1.5 HP Pump, Hayward sand filter
    Mineral Springs SWCG (it's actually Hayward/Goldline), Hayward Goldline T-CELL-15
    Polaris pool cleaner (with booster pump)
    TF-100, SpeedStir, K-1766 Taylor Salt Test, Lamotte Borate test strips

  7. Back To Top    #7

    Join Date
    Jul 2015
    Location
    San Marcos, CA
    Posts
    110

    Re: Does it matter where you take your water sample from?

    Quote Originally Posted by JoyfulNoise View Post
    It does to the extent that you want to get a sample of water from the bulk of the pool, not near the wall, not near a return and certainly below the surface by at least a foot.

    My only concern with using the spigot at the equipment pad (I have one to right after the pump but before the filter), is that you can't be sure of the water sample you are getting. If the pump is drawing from the skimmer mainly, then that water is mostly surface water from the pool which could be low in FC due to sunlight degradation. If there are main drains involved, then that's a little better because the water is coming from both deep in the pool and at the surface but it would be hard to know what the proportions are. Obviously getting a sample from the deep end using a long draw tube like a straw (with your thumb initially held over the opening) lets you draw a deep water sample. But I also empathize with your back and knees as I have had past back issues and it is not fun at all.

    So, you could try to take two samples of water, one from the pool and one from the spigot, and see if you can detect any differences. The biggest difference should be in the FC level as surface water will be depleted of FC from the sun. I would expect the pH to be fairly uniform. The TA might be noticeably different at the surface.

    I'd be interested to see how your experiment turns out....good luck.
    Water is drawing mostly from the barracuda, but some from the skimmer. Maybe 1/3 - 2/3 skimmer to barracuda. I don't have any chemical injection site (yet) and I make sure to purge any standing water before taking the sample.

    I like your idea of taking two samples and comparing the results. Of course, seeing no difference doesn't mean there isn't a difference, but it's a data point.
    16 x 32 IG plaster pool, 23k gallons, built 1992, DE filter, Pentair VS pump, IoThyngs controller, Taylor 2006 test kit, SoCal water restrictions
    Newbies with green pools, see SLAM and Recommended Test Kits. My company: IoThyngs

  8. Back To Top    #8
    JoyfulNoise's Avatar
    Join Date
    May 2015
    Location
    Tucson, AZ
    Posts
    11,591

    Re: Does it matter where you take your water sample from?

    Quote Originally Posted by Amail View Post
    Water is drawing mostly from the barracuda, but some from the skimmer. Maybe 1/3 - 2/3 skimmer to barracuda. I don't have any chemical injection site (yet) and I make sure to purge any standing water before taking the sample.

    I like your idea of taking two samples and comparing the results. Of course, seeing no difference doesn't mean there isn't a difference, but it's a data point.
    That sounds ok. In my pool I have the skimmer tied to the main drain as one line coming in and the Kreepy Krawly vacuum on the other line with a 3-way valve setting the split between them. If I drew water from the spigot in my pump, I'd probably get a good mix of surface and deep water. I bet it would be very close to the water sample I get with my 4-ft draw tube. Perhaps I'll test that someday and see.


    Matt
    16k IG PebbleTec pool, 650gal spa, spillway and waterfall, 3HP IntelliFlo VS / 1.5HP WhisperFlo, Pentair QuadDE-100 filter, IC40 SWCG, MasterTemp 400k BTU/hr NG heater, KreepyKrauly suction-side cleaner Dolphin S300i robot, EasyTouch controls, city water, K-1001, K-2006 and K-1766 test kits, Mannitol test for borates

Posting Permissions

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