"THEM" vs. TF100

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,589
East Texas
Small discrepancies I can understand. These I can't.

THEM TF100
FC 1.7 3.0 (before I added 1 gal clorox, circulated and took to them to test!)
PH 7.6 7.8 no issues
CC 0.0 1.0 (Major Issues)
CYA 25 45-50 (Major)
TA 113 160 (Major)

With estimated gallons within 500 of each other and THEM having a new machine, HOW can these numbers be this far apart? How typical is this for all the users here between what their test kits say and what "THEY" say. My TF100 is barely a week old, so it can't be the age of my chemicals.

This just confuses me to no end and makes me question my numbers (or theirs). I'm old and senile, but I can count drops!
 

frustratedpoolmom

TFP Expert
LifeTime Supporter
In The Industry
May 20, 2007
12,226
SWSuburban Chicago, IL
Pool store testing is notoriously innaccurate and inconsistent. There have been literally thousands of stories like yours on this forum alone describing testing such as this.

Trust your own tests....that's why we recommend the kits in the first place. :)
 

poolgirl22

Platinum Supporter
LifeTime Supporter
Apr 14, 2010
595
Stephens City, VA
You have discovered the secret of poollife...the inconsistent pool store result. Which is why so many of us have been on the merry go round with the pool store.

Take tap water in sometime for some true entertainment. I've never done it as I live in a small town and don't want to get labeled...but I've read about it...tap water with CYAs of 50-60...etc.

The test kit is the key...because it's consistent...
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
22,069
San Dimas, CA (LA County)
I suppose to be charitable, some of the difference could be in the travel time.

Could be haste. I believe those machines have to be calibrated to compensate for the cloudiness of the water. And if the bottle itself gets dirty with residue, thumbprints, whatever, it's going to affect the optical reading, too.

Trust your own kit. And returning to haste... I'm guilty. I just got a speed stir and things tend to get mixed better and longer with the new toy than with my wrist. My readings changed dramatically, especially CH, using the stirrer. You might consider ordering one when it's time to order refills for your test kit.
 

poolgirl22

Platinum Supporter
LifeTime Supporter
Apr 14, 2010
595
Stephens City, VA
Richard320 said:
I suppose to be charitable, some of the difference could be in the travel time.

Could be haste. I believe those machines have to be calibrated to compensate for the cloudiness of the water. And if the bottle itself gets dirty with residue, thumbprints, whatever, it's going to affect the optical reading, too.

Trust your own kit. And returning to haste... I'm guilty. I just got a speed stir and things tend to get mixed better and longer with the new toy than with my wrist. My readings changed dramatically, especially CH, using the stirrer. You might consider ordering one when it's time to order refills for your test kit.

I dunno...my store kept trying to tell me my gallons were about 5k more than what they were....I've been at 16100 for 7 years. Internet, other store, literature I found in the pool house, more internet sources...16,100...yet all of a sudden my gallons were over 20k...hmmm.....sell more product maybe?
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,589
East Texas
My travel time to the pool store is less than 5 minutes and they checked it as soon as I walked to the back. I didn't set the sample on the hot dash board either!
 

flyweed

Bronze Supporter
Aug 3, 2009
525
SW Wisconsin
trust your own tests..forget about "THEM"...if you want a really really accurate measurement, go to you local county courthouse, or gov't building they all have a health services dept. WITH a lab that tests water samples...they will give you a sealed, sterile bottle to bring in a sample....take it back to the lab, and they'll test it for whatever you want..there is a fee of course, but you aren't going to get more accurate than lab tests in sterile conditions.
 

primetime

LifeTime Supporter
Jul 28, 2008
58
Sinking Spring, PA
For what it is worth here is what I do.

I use the TF-100 test kit. Once a month or so I take a water sample to Leslie's (I use them because they use the drop tests that are similar to the TF-100). I test my water before I take it to them. I have found them to be very close to my results. This gives me a certain comfort level with my own testing. I actually go with their pH reading because they have a nice little light that really helps you see the color. I always ask to see it and they let me come behind the counter to look at it. I do usually buy something when I am there, but their prices are a little high.

I also take my water to my PB once a month so they have a record of my water. They currently use a system with little vials that they add my pool water to and then put it in a reader. I always test first. Except for the FC test they are pretty accurate also. Just today I was there and they told me FC was 2.2. I told them that was wrong it was 5.0. The guy tested with OTO and said my number seemed more correct. He also told me they were getting a new super duper Taylor test system that is suppose to be state of the are. I will let you know what I think of it the next time I get my water tested there.

I now trust my own TF-100 test over anyone else's!!!