Taari - Not RRF
Firemedic269 - Not RRF
chris.rivera3 - That's RRF
mistahoo - Not frogbit. That's water lettuce
bluestems - I think you nailed what Taari has.
RRF propagates through runners, creating great big chains of RRF, not 4 leaf clusters. New leaves tend to curl up at the sides and overlap existing leaves, and with proper lighting you get little white flowers.