I understand what I need to add to the tank and why.
Micro is your trace elements, Macro is your nitrate/potassium/phosphates.
I realize I can get Micro from bottles sold at the LPS. Flourish etc?
But what about Macro's. how do i actually add them to the water? where do I buy them?
Some links to actual products would be nice, as a starting point - its like telling me my fish tank needs water, but I have no concept of getting water out of a tank..

how should I know what do i do?
thanks
edit:
reason I ask is because all my plants are showing very pale/almost white new-growth.. I read this is due to lack of nutrients.

I have used Co2 injection heavily when I first set the tank up and my thought is that the plants used up everything in that time. (I dont co2 inject any more, and its only been 4 or 5 days since I stopped.). I will be doing co2 injects eventually though, just going to wait till I get a furuval co2 kit - I cant be bothered with the mess of DIY kits