I bought some white LED night lights for $1.50ea..
The circuit is different then the other white ones cause it is photocell and not on/off switch. Long story short I got the red LED to work off the circuit and was feeling quite accomplished... stuck it in the container and shortly after POP!! You know that sound when metal turns to vapor. I didn't insulate it well enough and the AC arched, yeah that red LED is fried now. Where it arched there is a chunk of metal missing.
It looked perfect with one blue one red and one white LED, now its back to white and blue.
I'm going to make a 2 liter Micro Grow. I'll use 3 or 4 white LEDs. I bought a "patio" tomato to grow in the 2 liter.