This sounds like it should work. Do you know the resistance of the LEDs? You need to know some of the LED specs before you can be sure of what will work. You can use one of the handy on-line LED calculators (just Google for it) to calculate the proper resistance to add for LEDs in parallel, series, or in combination.SF Jack, I think I'll use 2 green LED's in series with a 9 V battery and 1K ohm resistor in the line. That way I can put the circuit with the battery and a switch just below the base of the layout and won't have to run extra wires out there. Do you think that will work? I found a nice large area for the pool close to the reactor by moving things around a little. I might try some other colors too and see what the effect is. Thanks for the idea. bob
I think that if you add a larger resistor, the light will be dimmer. At least, that's what I would expect. So you could achieve a subtle glow that way. I'm going to try some orange ones in buildings at night.