I bought this plant at a pet store. It came in a plastic tube with its roots in a clear gel that is said to be fish safe, and the plant itself is said to be "snail free." It was called an "Aqua Fern" and sold as an aquatic plant. I brought the plant home and looked it up. I read the Trichomanes javanicum is not an aquarium plant; it is some type of fern terrarium plant and is expected to die within weeks of aquarium planting. It is a fern that enjoys humid conditions, but will eventually decompose underwater. The label on the plastic container it came in is not clear as to the care of this plant. It does refer to the plant as a "Live Aquatic Plant" and was sold in the fish section.
This is what the label on the back of the tube said:
"In addition to adding beauty to your aquarium, live aquatic plants offer many wonderful benefits. They provide natural hiding places for fish, reducing nitrates in the water, and provide a food source for herbivorous fish. Choose a variety of plant types and sizes to create a beautiful, natural looking aquarium.
Directions for use:
Remove green tape from bottom of plant container.
Remove the small plant container from larger container.
Remove plant from gel and rinse off excess.
Prune discolored leaves or stems.
Your plant is ready to be placed in your aquarium."
Nowhere does it mention this plant is a terrarium plant. The more I Google it the more I find things like, "Not a true aquarium plant. If kept in the aquarium it will slowly rot, die and pollute your tank."
It is not recommended that you add this plant to your fish tank.