Flood lights is an option as well, cool white in the 6000K range but you'f got to find a way to mount it over. If the tank has a glass lid, some just pop them on top facing down.
I was seriously considering one of these but I found online that they grow more algea than plants
If the light unit grows algae, it will also grow plants. You just need a way shorter photoperiod to prevent algae outbreaks.
Low light plants still need a good enough amount of light. There is such thing as light compensation point below which plants don't grow and eventually die.
Basically, most people that have no success with low tech tanks is because they don't provide sufficient light. You don't need excessive light for low light plant but you certainly need enough, and and as a reference, the amount of light needed will be bright enough for fish that don't like light.
Basically, the only plant I'd recommend in very low light conditions is anubias. All the rest of my plants pack bags in such conditions.