It's really easy to make a pond light out of a headlight, it will take
you an evening to make it, plus a day or two for the caulking to cure. You
can buy aquarium calking at orchard supply & hardware, or most petstores. Do
not use regular kitchen/bath/window calking, most of that specifically says
not for marine or aquarium use.

Before you begin the project, to see what kind of garden lighting system you
have. If you have a low wattage transformer from Intermatic or Malibu, it's
usually not grounded, The grounded transformers are rated at 300watts or
higher, for their product line. Next add up the wattage of all the bulbs
connected to the transformer, it should be less then the rating of the
transformer. Once all that's done, follow the directions below, and you're
done.


I purchased a sealed beam, Sylvania H4656, which is a combination of high
and low beam in 1 unit. A high beam only would have been desirable, but I
couldn't find any that had prongs that were convenient to solder the wires
to.


If you look at the back of the bulb you will see 3 prongs


high low
O O
O
ground


A side view of one of the prongs, looked like this.
--------\
O |
--------/


Connect 1 wire to the ground, and 1 wire to the high beam prong. The solder
didn't bond very well, to the prongs, so I found it easier to thread the
wire through the whole in the prong, and wrap it back around itself, and
solder the wire.


Cover all prongs with aquarium caulking to prevent corrosion. Note: Do not
use kitchen/bath/window caulking, most of that stuff isn't safe to use in
ponds. Let it cure in the sun for 2-3 days, then wash it off. Aquarium
caulking can be purchased at most pet stores, but is cheaper at hardware
stores.