Has anyone here actually tried to cultivate copepods in this manner?
YES! me along with many of us every day for a LONG time!
Is there a general guideline which could point me in the right direction aside from the cultivating solution being "green?"
NO
it takes experience, which i do realize is something you dont have yet
at first you do have to add a lot of phyto, but not 3gallons as for an example of a how much green if its as dark as an empty mountain dew bottle under bright light its more than plenty, though not specifically too much, its more than you need. wait a day, see how much it changes if its clear you needed to be darker, if its a very very light tint then thats about right, if its darker then you gave too much.
secondarly you should try IA (
http://www.instant-algae.com/) they are located near the bay area