Just a little update, I ended up using one 10,000k bulb and one 5,000k the color looks better and it isn't all that bright in the 90 gallon. When I had the two 5,000k lights, it was a little too yellowish for my liking.
The water sprite isn't going to make it. It was doing great at first and I noticed some growth, but recently my fish have been snacking on it constantly. It's just being torn apart at this point.
I have a few other plants in the tank that are doing OK. The Amazon sword has a bunch of bite marks on the larger outer layer, but the inside is growing strong daily. I think it'll be OK.
Put the water sprite in a breeding net and let it grow, when it gets too big you can put some in the tank for the fish to eat.
If the fish are eating the plants, offer them algae flakes or pellets, and try them on pumpkin, zucchini, peas, carrot. Make sure they are free of chemicals. You can either cook them or feed them raw, most fish like them partially cooked so they are softer.
You can grow Duckweed and Water Sprite outdoors in plastic tubs, and when you have plenty, move some into the tank for the fish to eat.