Wait so do you mean to just use flourish or flourish excel?
Well you could be using both. Flourish Excel is a carbon source for plants to use (Although in most cases, it is not recommended to use Excel in place of good 'ol Co2). Regular Flourish will provide you with much needed micro and trace nutrients. I'll let you find out what those are, I think others can do so much better than I can.
Here are a couple of links that should help you out with stuff, and definitely helped me when I got into the hobby. These websites have been up for years and the info on them is top notch.
site has lots of good info, and he has also started selling planted aquarium products.
Another good website is Chuck's Planted Aquaria Articles
. I did lots of reading on this sight as well when I first started in the hobby.
But more than anything, use the "Search" button on the forums. I think you're best information will come from this forum. Read Read Read. I know its a lot of time and research, but I'm sure you're used to that having had saltwater tanks
Good luck. If you have any questions as your learning, feel free to ask
Your tank looks nice, are those Wisteria stems? I suggest going through and looking at everyone's different setups and deciding on some scapes that you like. One company you'll hear a lot about that has come to be very popular recently is ADA
. They make exceptional, and what some would argue "overpriced" products. But in any case, if you check out some of Takishi Amano's aqua scapes, you're jaw should drop a little on some of them.
As for suggestions, I don't have many. (I spent probably 2 hours just trying to decide which way to arrange the rocks in my tank. And I only have a 2.5!) Maybe you could move the rocks around to create a focal point using the "Golden Ratio" (Google it if you're unsure of what it is). Eventually you could try wrapping the rocks in Riccia, Mini Pellia, or some other similar plant.
Well, thats all for now, see ya