Originally Posted by Aurie
I had about 40 ferns, I traded all but 3 into my LFS for a credit. I decided then to dose my 10 gallon tank with a couple drops of excel and and within 24 hours my 3 plants are almost gone! I've done 2 water changes and that seems to help but the damage is done. 2 plants are toast but my big one barely survived. No other plants were harmed. I can only assume it was the excel so I'm not using it on that tank again.
As Boredomb said, Excel can be dangerous. I do not recommend it, or any other "carbon" supplement.
Java Fern being a slow growing plant does not require much nutrient supplementation, or high light. The CO2 naturally occurring in the tank will be sufficient.