Here is the link on TDS & EC
http://boards.cannabis.com/showthread.php?t=61763

Ph, the first thing you should know is.

It sucks to play the Ph up & down game so only add very small amounts at a time. Then mix it up and check the level.

You can always add more drops at a time if you need to but it's a bitch to switch from up to down and get it to balance. Start with just a few drops at a time until you get the feel for how much buffer you have in the nutrients you use. It will not talk very long to get the handle of it and figure out Ph-ing.

Small steps at a time to start with.