Thank you for the response!

Everything I have read seems to indicate that increased CO2 levels will hault the growth of BBA.

My substrate is clean and I don't leave old leaves hanging around. Over the last couple days I have been increasing my CO2 levels until fish show signs of CO2 related stress (hiding, rapid breathing and/or faded color). I'm going to find the tipping point and hold it there. The excel has done yet another excellent job of destroying the BBA that was present previously.

I'm amazed how much CO2 can come ramming out of my ceramic diffuser .... however I have only a basic small one (similar to a ADA Pollen Glass Large 30). Would I benefit from going to a Beetle 50 or something like that with a larger diffusion surface area?

Thank you,