Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
You can use liquid carbon. I would try half doses first, and see if the Rams react. They shouldn't, but just be ready to do a water change if they do not like it.
If they are OK after a week of half dosing you might increase the dose, or just wait until the fry are free swimming.
I would not do the double dose that Seachem Excel says to do after a water change.