Join Date: Jul 2013
Location: Gainesville, FL
The ammonia can be registering from broken up chloramines if you're water is treated that way and you're (hopefully) then using a dechlor product that works on them. Depending on when you test that may be getting picked up...or there's something else in the tank that is decomposing/producing N waste/leaching.
As for the java fern that's definitely a quick way for them to reproduce. I have a regular that's been melting ever since I got it...the way the roots were bound I can't tell if the rhizome is still healthy or not, but every leaf that has melted has been producing daughter plants beforehand, so it thought the conditions were right or at least wanted to give it one last shot.