Hornwort will grow in just about any light or condition. There's two types: a coldwater and a tropical variety. The former (which is probably what you have) is more widely available and will shed its leaves in your tank for a little while as it adjusts. After that period, you're golden.
I have salvinia minima as well and I found that it didn't really start growing until I upped my lighting from a 10watt 6500k CFL bulb to a 14watt 6500k CFL. I also started dosing Tetra Florapride (in addition to Flourish once a week) on a regular basis in that tank at the same time so I don't really know which really helped. Point is, after I made those adjustments, the top of my five gallon was literally covered in about two weeks.
So, to answer your question, I don't really know if salvinia will survive in a tank lit by LED lights, but hornwort more than likely will. Hornwort doesn't need any special care, really, but if you plan to really get into plants Seachem Flourish would be a good investment. (:
Last edited by colorxmexravyne; 07-15-2013 at 09:11 PM.