I want to build an light fixture for my aquarium and decided to use LEDs, almost everywhere it's suggested to wire the LEDs in series. but that will need a high voltage for many high power LEDs. also if one of the LEDs in series for whatever reason burnt, all LED's will turn off.
The main reason to wire LEDs in series (if I understand correctly) is because of the manufacturing variation in LEDs, that may cause one LED pull more current than the others if wired in parallel.
Let's assume that we've 5 LEDs, each needs 1 V / 10 mA and it's connected to a power source which provides 1 V and 60 mA constant current:
In above diagram each LED can't pull more than 10 mA and resistors will not get hot either because the power source have a current limit.
But what if the little variation in LEDs cause one LED to pull less current than the others? what's the solution for that?