Thanks folks, not really wanting to run them at there optium brightness, just trying to understand the theory.
my understanding now is, Just 1 RGB Led (3 Diodes), can require 60ma in total (20ma each diode) when all are lit.
with the following resistors (2/3/3)v
Red : 5v-2v / 0.02a = 150 ohms
Green : 5v-3v / 0.02a = 100 ohms
Blue : 5v-3v / 0.02a = 100 ohms
but you cannot use the above resistors, before this would overload the arduino since it can only supply 40ma from a pin at a time and since the they are using common anode on the 5v pin.
The circuit I have is
with the following resistors (2/3/3)v
Red : 5v-2v / 270 ohms = 11ma
Green : 5v-3v / 270 ohms = 7.4ma
Blue : 5v-3v / 270 ohms = 7.4ma
Total 25.8 ma well within 40ma pin limit.
Last question....honest, I thought LED's had a limit that they only activated(switched on) at, is that a Volt Level or Amp level?, just original confused as I thought you need 20ma minimum to get then to light up, I didn't know you could run then at lower current levels.
Thanks for all your patience. own you guys.