My start up Numbers

[BigDave]

U R Awesome! - don't forget it.

[bssage]

New numbers

FC=9.8
CC=0.4
CYA=56
PH=7.4

These are close but not exact to your recommendations Dave. The ambient temp is going to keep us out of the pool for probably better than a month. Should I keep trying to fine tune these numbers? Or let them ride for a bit? I do want to put the solar cover on as soon as I can to reduce delay's when the warm weather hits.


For some unknown reason. I end up testing PH twice. The first reading is almost always low around 7.0. The second reading is typically around 7.4 or slightly higher.

[BigDave]

Since you report 9.8 for FC and 0.4 for CC, I presume you are using a 25ml sample for the chlorine test. You will conserve your testing reagent by testing with a 10ml sample ( and multiple by .5 instead of .2 ). You'll burn through the drops really fast with the 25ml test.
How do you come up with 56 for CYA?

You can let it ride if you want to, as long as you keep the FC above 5 all the time and your CC is 0.5 or less and your don't lose FC overnight - you're OK for chlorine. Fine tuning is something to avoid - the goal is to get your numbers in range, not exact. You can go bananas trying to get "perfect" numbers but it's pointless to try. Anything in range is perfect.

pH is weird, do you rinse the test tube with pool water before collecting the sample?