Hi, I want to buy 5 meter 60 LEDs/m LED strip here and this is the recommended circuit. The strip needs 5V. In their description they say 60 LED is 18W so I need 20A DC power supply. Can I send 20A 5V DC directly in the strip? Will it fry the strip? Also, for the ground wiring, is this where the electrons come back in the power supply with 0V? If so I suppose I don't need a big AWG wire? How to calculate how big AWG I need for ground wire?