Thanks for the kudos, Nathan.
And you're right; there are low voltage garden lights, but I'd suggest using the LED solars which CAN use any rechargeable battery (mine use AA)and be done with wires. These lites I'm using can be in or out of water, so one can also go the above route too. I use the rechargeable solars for above water/garden effect and the underwater LEDs for water effect. I'm not trying to light up the whole pond to see fish, though, I'm using the lights for effect. When the fish swim through the light, it's a ghostly effect and just adds to the overall ambiance. Looked much better when all the plants were mature, and I'll post more pics prob about midsummer, just to show that 'look'.
Jen; really should look into the LEDs as Nathan suggests; best use of power consumption (and therefore cost) as well as inexpensive ($10 a unit, compared to approx $3-4 for battery/garden units) and the light is fairly bright. I have to tilt my underwater ones down so as not to 'blind' viewers looking into the pond. The waterfall (blue portion in the pics) is lit up by 3 of the units, all facing one tier of the falls each, and is quite vivid, imo. Also, any light is going to show floating particulates, if you have them, so best to create the clear water if you want nothing but fish and light to be on display. What I especially liked is when the plants are mature, their undersides is lit up and interesting patterns emerge.
Michael