when to begin nutes?

my plants are 12 days old when is it safe to start useing nutes?

When the 2 round leaves (cotyledon) turn yellow and dry up...
You can then start feeding diluted Nutes...
Start off with 1/6 the recommended dosage..
Build it up over the next 2 weeks..
If you see any sign of nute burn on your leaves,back off the nutes for a wk, then reintroduce very slowly..

even if the recoomended dosage is 2.5 ml/gal for flora nova?