Yes. That's right. It also helps to keep the algae at bay to an extent. I came across a thread at Tom Barr's site stating that most moss,Hydilla and Elodea dont thrive that well with excel. I am sorry if i am intruding in your post but i really need some help. I am planning to soak Aqua soil amazonia for 2 months to cycle it and get rid of the ammonia. Then flood the tank and plant Christmas moss. I was wondering also if it would be possible to start straight away with a nonco2 environment this way. Sorry if all this sounds silly and dumb.