Newbie growing Legend tomatoes

[Talon1189]

Hello......I am new to growing tomatoes from seed. I live in Michigan. I bought some Legend seeds off the internet because I read that they are large tomatoes that are listed as a 68 day tomato with good late blight resistance. I just planted them in an old ice cube tray with Scotts lawnsoil from a bag in my garage. I am starting them indoors. I put the seeds under a high lumen aquarium light intended to grow plants in a 55 gallon aquarium. How much light should I give them daily? I intend on planting them in some Topsey Turveys in early May if the weather is warm enough. I will be growing only 4 plants as I live alone and that should be more than enough. Any other advice and suggestions to me would be greatly appreciated