Pool school and Poolmath question


Well-known member
Aug 17, 2014
NW Ohio
Ok, I struggled this year keeping my pool water in check.

I am going to take a crack at learning how to use this poolmath.

The poolmath link says to first estimate your pool volume. My pool is 22x32x4.5 so about 24,500 gals.

Next I see the recommended levels for a vinyl bleach pool

FC 3-7
PH 7.5-7.8
TA 70-90
CH 50-300
CYA 30-50

Third, this is where I get confused, it says to enter your current test results in the NOW column. There is no NOW column on the POOLMATH page. I see GOAL and NOT SETUP? Am I missing something or are the directions incorrect?
NEVERMIND - I see at the bottom I have to specify the pool type and whatnot. NOw I see the columns with the goals.
Also, I have the TF100 water test kit and I found it difficult to get some of the readings, like the black dot test (CYA). I am willing to take my time again next spring I also had some older bleach and would add a gal and 2 days later have no FC, likely due to my missing CYA but I added a full container of conditioner.


TFP Expert
Platinum Supporter
May 23, 2015
Tucson, AZ
Take your time learning how to do the CYA test as it is critical to know what that level is. Mix the reagent with your pool water in the dropper bottle provided and then make sure you are in bright outdoor lighting with your back to the sun and the view tube waist/belly high. Add the test sample until you see the dot disappear. Keep both eyes open and pinch-hold the test vial so that your fingers are not obstructing light from getting through. You can pour the test sample water back and forth between the sample mixing bottle and the view tube so as to do the test multiple times until you feel like you're getting a consistent value.

If the test solution is clear and the dot never seems to disappear, then you probably have very low CYA. If the test solution is very milky and the dot disappears almost right away or your read 100ppm as your CYA, then you probably have more than 100ppm and you need to do dilution testing to get an accurate value.

The sample water from the pool needs to be at or above 68F for the test to work right. So if the pool water is cold, bring it inside and let the water sample warm up first.

Always add the reagent to the water in the mixing bottle and gently invert mix the sample for 30sec (do NOT vigorously shake). Then let the sample rest for 30secs and give it one more invert mix before pouring into the measuring tube.

You can also purchase a 50ppm CYA standard solution that you can use to "calibrate" your eyeballs and lighting conditions to help you find the perfect spot for testing.

Sent from my iPhone using Tapatalk


Gold Supporter
TFP Guide
the best way i found to do cya test was posted here a couple of years ago
after mixing reagent
fill test tube to 100 mark
then hold at waist level with back to sun and have a glance
if you see black dot fill to next increment and repeat
if you add drop by drop and keep staring you see the outline even when it is gone