Planted Tank Obsessed
Join Date: Feb 2004
Location: Westchester County, NY
Well...interesting because you're willing to spend some good money so that isn't a limitation. The first of the two light units seems to come stocked with 14,000K bulbs which I'd discourage you from getting. For plants, you'd want a lower K-rated bulb...I personally would go with 10,000Ks though close to 6700Ks are generally considered the best for growth. They throw a very yellow color while the 10,000Ks throw a whiter light that I personally find preferable, but to some extent, it's a matter of taste so ask around and look around on that issue before you make a decision.
As for the LED unit. I don't know that I disagree with epicfish, that it's an awfully high price for lighting, but it is the "state of the art" and I like that if it's affordable for you. I can also tell you that despite the 20,000K rating on the lighting in the LED unit, I have seen them on a planted tank and the color rendition is very nice (and not hopelessly blue for a planted tank as 20,000Ks are, IMO) and the plants that are growing under them are growing very well and look great. So, from what I've seen with the LEDs, it's a good choice for you.
I'd add that I have six 39-watt T5 bulbs on my 36-inch 58-gallon planted tank. While I, like many other people do get good results from T5s, I personally think that you'd be better off with metal halides or the LEDs that you're considering. If I were to choose a new lighting fixture I'd go with MHs or LEDs. Just be aware that the metal halides do generate a lot of heat so if this is a potential problem in the room that your planted tank will be in, in the warmer months, stay away from the metal halides.
As for substrate, I can tell you that I recently tried the Amano two-layer substrate and it was downright awful for me in my experience. I pulled it all out and switched to Eco-Complete which has been terrific and I recommend that.