Yes, CFLs are great. Those that he uses there are only powerful 6500k out there too. And they are cheap...
Walmart
Sounds like you do not have any kind of lighting currently. Do you have a hood at all? I make a cheap hood with similar CFLs in this thread...
DIY Light Canopy. I have pictures there too.
I have nothing protecting the bulbs from splash, they are still working strong though. They have created a little bit of build up of
calcium I think on the bottom closest to the water. You could block water splash by using a glass top to the tank.
The heat will not be a problem cause they produce little heat and with the foil , very little will even get to the plastic. I have a 19 watt CFL on a small 5 gallon tank with a plastic hood with no problems with the plastic.