So I'm fairly new to aquarium planting and I just bought some aqua ferns and some unknown plants at Petco for my tank. In addition to adding some sneaky snails to my tank, I've also just done some research and found out from plantgeek.net that the fern is not a true aquarium plant and will slowly rot and die in my tank. Is this true? And if so, the why the hell do they have tanks of this stuff at Petco for SALE?!