BerlinKowgirl, it seems you have had some experience in saltwater...a technical challenge for sure, so I think you have the "tools" to be successful with plants too. It looks like you are off to a great start here. The big key once flooding this will be keeping the CO2 high while the plants adjust to submerged conditions. It will minimize the melt of the HC while it transitions to submerged life. Took me a few tries to get HC right, it was all related to CO2. Your glass diffuser is nice and should work fine for your small tank.