I have had Frogbit, but it ended up melting away/outcompeted as the seasonal lighting changed and the water got cooler. In a static environment it still required nutrient rich water. It did much better in a heavily populated tank with some air stone movement to the surface on one corner of the aquarium and warm water at least 78 degrees. It did not like full sun, I grew it in my tanks in the shaded portion of the greenhouse where it only received indirect light. I use a mixture of Water Spangle Salvinia minima/duckweed/dwarf water lettuce and of those 3, the water spangle is the easiest and most tolerant of diverse growth conditions. Salvinia also can be easily collected from the surface of the aquarium if you need to remove it.