Im using this code with 30 leds but its not bright enough? I Dont have any more relays ect, If i put the brightness on a scale of 1 - 10 its 5, but when I hook it up to a 9v battery its bright 
/*
Blink
Turns on an LED on for one second, then off for one second, repeatedly.
This example code is in the public domain.
*/
// Pin 13 has an LED connected on most Arduino boards.
// give it a name:
int led = 13;
// the setup routine runs once when you press reset:
void setup() {
// initialize the digital pin as an output.
pinMode(led, OUTPUT);
}
// the loop routine runs over and over again forever:
void loop() {
digitalWrite(led, HIGH); // turn the LED on (HIGH is the voltage level)
delay(43200000); // wait for 12 hours
digitalWrite(led, LOW); // turn the LED off by making the voltage LOW
delay(43200000); // wait for 12 hours
}