I would get play sand and potting soil (not sure on the brand of soil OFL would know though). What you do is line the tank with play sand and then put the soil on top and then put your plants in the soil. Once their planted you cover it in a good layer of sand. It'll take a while for everything to get chemically figured out but they look really nice and grow very nicely. OFL has done this in a 55 gallon an it turned out wonderfully
Feel free to message me any questions, I'll try to help the best I can!
Rummy- Mini Rex Rabbit
Diz jr- Betta
Yoshi- Crested Gecko