I add the extra k-meta at bottling. I mix it up in 200ml of cool water, put it in my receiving carboy and rack onto it. Then I filter to a primary fermenter and bottle from there.
If I am going to bulk age, I rack every 2 months and I add the k-meta every other racking (based on a quick free SO2 test). Before I bottle bulk aged product I test for pH and free SO2 and use this table as a guide line.
http://www.accuvin.com/pHSO2Links.pdf
Also, if you invest in a digital pH meter you can follow the procedure below first presented by board member Joesph.
"If you are going to get a pH meter, you can place the Acidometer on the shelf with the other little used equipment. First put your sample in a 50ml beaker and take your pH reading (the meter must be calibrated first). Then to determine acidity, slowly add sodium hydroxide (using burette, pipette or syringe), stirring as you add, until you have a pH reading of 8.2. The titratable acidity of your sample can thenbe determined with the following formula:<?
amespace prefix = o ns = "urn
chemas-microsoft-com
ffice
ffice" /><?:NAMESPACE PREFIX = O /><?:NAMESPACE PREFIX = O /><O
></O
>
<O
></O
>
TA = 75 * V * C/VS<O
></O
>
<O
></O
>
Where:<O
></O
>
<O
></O
>
V = volume of sodium hydroxide needed to obtain a pH of 8.2<O
></O
>
C = concentration of sodium hydroxide used (0.1 normal or 0.2 normal)<O
></O
>
S = volume of the sample of wine or must<O
></O
>
<O
></O
>
For example: you have a 15ml sample of wine and add 12ml of 0.1 normal sodium hydroxide solution to reach a pH of 8.2.<O
></O
>
<O
></O
>
TA = 75 * 12 * (0.1 / 15)<O
></O
>
TA = 6.0<O
></O
>
<O
></O
>
The acidity of the sample is 6 grams per liter (6 parts per thousand or 0.60%). Note that this formula will also work if you use Phenolphthalein indicator solution since the color change occurs at pH 8.2
<O
></O
>
Play with the formula to adjust the sample and the concentration of sodium hydroxide solution. For example; if you use a 15ml sample and the concentration of sodium hydroxide is 0.2 normal, each ml of sodium hydroxide added translates into one gram per liter (0.1 %) of titratable acid.<O
></O
>
<O
></O
>
Make sure the sodium hydroxide solution is fresh. It has a limited shelf life and begins to deteriorate once the bottle is opened. Buy the smallest bottle possible. Buy in bulk only if you plan to do a lot of testing in a short period of time. The alternative is to add to your lab and standardize the sodium hydroxide solution before using it in your test."<O
></O
>
Edited by: Coaster 
