Yeah what I found with my Java Fern
is that the pre-existing leaves you get from the store tend to gradually die off, particularly the older leaves. Watch for plantlets forming on the tips bigger older leaves, because these will all grow into beautiful little individual plants eventually. I've had my Java Fern
since May, and it was sold as a "mother plant" because it was producing lots of plantlets. Sure enough most of the original leaves are gone or dying, and basically all of the Java Fern
you see in my aquarium pictures on the left tab developed from little plantlets.
Your tank needs more fast growers though. I'm not sure what species that stem plant is, but you might want to add something like Brazilian Pennywort
, which works well planted in the substrate or left to float, and Water Sprite
which is a favourite plant of many on these forums.