Here are my current numbers...


TC 6.5
FC 6
pH 7.2 (recent acid addition)
CC .5
TA 150
CYA 90

So let's say that i want to knock the CC down to 0. How do I know how much bleach to add? I must not be smart enough to get the calculator to tell me or i am using it wrong.

That isn't one of the questions the calculator can answer directly, though it will give you a couple of hints along the way.

Since CC is 0.5 or lower, there is no need to shock. Eliminating low levels of CC can be done by aiming for the high end of the recommended FC range.

The first thing to do is to look at the Suggested FC Levels for your CYA level. Then use the high end of the normal range as your target FC level and calculate how much bleach you need to add.

Also remember that if you are using a 10 ml sample size, then seeing pink that clears after one drop in the CC test means <= 0.5 ppm and doesn't mean 0.5 ppm. If you were to use a 25 ml sample size, then this would have resolution and accuracy to 0.2 ppm and you may find that the pink still clears after one drop meaning you have <= 0.2 ppm which is certainly nothing to worry about at all.