If you go
more than a 20 milliamp draw then you will have to calculate the series resistance and add in a resistor. You can use either a single LED, two LED's, or a single multicolor LED. As I said before I use two LED's: One red and one green, but you could use any color that strikes your fancy. A 20 milliamp LED is fairly standard.
Which Aquaero version do you have and are you using Aquasuite?
Shoggy would probably be a better one to talk to about the Aquasuite as I haven't used it for many years.
Here is a
LED calculator and here is a
LED tutorial.
Pin assignment: Pin 1: VCC LED 1 (whatever color you want)
Pin 2: VCC LED 2 (whatever color you want)
Pin 3: GND (you only need one wire for both grounds if you are using 2 LED's.
Here's my setup on my front Aquatube.