yes be cautions of what planst you bye from lfs..sometime owner dont know better think the plants they got from wholeseller is a aquatic plants but actually isnt. Bring a small handbook about aqua plants if you go to lfs. That way you know what plants to stay away from.Better yet choose the planst you want to buy now before you get it.Different plants have different requirements. Dont buy them just because it looks beautiful without special care it will die/melt etc..that means your money is flying away.
If you want some low-mid tech i say 2 watts per gallon and up but you have to stick with plants like annubia,ferns,crypts,swords. Those dont really need ferts but of course it would be better if you added.