The 5V/10A power source is working fine, I have not tested it with a meter as I do not have one however when I plug it directly into the power source jack on the arduino itself (the jack to the right of the USB input) the arduino receives power and the LEDs light up.
If I was working with this many LEDs I would just power them this way however I will have 111 LEDs at the end so this is not feasible as the arduino regulator cannot handle this.