I didn't have algae problems till I got the fugeray ray2 led's. I had them wayyy too close. Don't have the 18 watt anymore. I'll do a thorough vacuuming when I get more root tabs which should be delivered soon. Nitrates are 0-.25ppm.
Cut out 1 or 2 rectangles of window screen to put in front of the Ray2. I had to do this when I got it for my 20H. One layer will reduce the light intensity by like 50% or something. It's an easy cheap solution that just requires the window screen, scissors, and double-sided tape.
I eventually hung it like 10" above my tank and don't have any algae issues. You should get some amano shrimp or RCS's to munch on the algae.
Your swords look fine, you don't need to fret about them. I have a red melon sword also and they are a dark shade of maroon, but the leaves have no stem. I like how your leaves have some stem on them.