What type of aquatic plants should I consider when setting up a 15 gallon freshwater tank?
No amount of plants is too much, but make sure your tank is fully cycled before you add all of them. You should get 2 watts per gallon of 6500 K fluorescent lights, that will give you a low/medium tech tank. The more plants you give it the less likely you’ll be to have algae outbreaks. If you do have algae and don’t want to do CO2 diffusion, you can dose with Seachem’s Flourish Excel to keep it away. In addition to the plants you listed, also consider fast growers like water wisteria and water sprite to suck up the most toxins and nutrients, anubias for easy care plants, and crypts for their diverse textures, shapes, and subtle colours. The most common stocking guideline is the inch per gallon rule. It applies to slim-bodied fish like you mentioned, and applies to the fishes’ adult size. Not everyone agrees with this rule, in fact it’s more of a guideline, but it’s the best way, in my opinion, to keep your nitrogen cycle healthy. The nitrogen cycle of course is the most important part