I have 3 types of Amazon sword plants in my 90g with 2 65-watt 6700K compact fluorescents. They are all doing very well. One is so big now that the leaves are against the front and back glass. Some Amazons get huge. I wish I had a 2-foot wide tank to keep it in. I do use plant tabs every 3 months for fertilizer.
Amazon swords are not very light demanding. They will do fine with a twin fluorescent bulb strip over the tank. They like a deep and rich substrate. Use some rocks to terrace your gravel so that it's about 3 inches deep where you want your sword. If available put a clay ball under the roots. I also use Jobe sticks for ferns (avaialable at garden stores) about every two months.
When planting snip the roots to about 1.5 inches and make sure they are not bent double during planting.
If the sword likes your setup it will grow to about a one foot diameter, so take that into account with your aquascape. I think a sword in one corner and a red lotus in the other looks good, as they are both large plants, but very different in appearance.
I have a sand substrate but I have waited for it to gain nutrients over the past four months to plant anything. I wanted to put one near my filter intake to cover the monstrosity the FX5 posseses. How do fertilizers work? Do you just stick them
Into the substrate?
Amazon swords will do well under almost any light you give them. The growth rates and size will be different. I cut runners off mine and plant them in low light tanks with a root tab. The two in my high-tech setup have leafs that are close to 2 feet in length and have a new leaf pushing out almost every day. 90 gallon tanks are pretty tall so it may take more light to break through the water if you want a good amount of growth.