What was the fern?
If it's peacock fern like I've seen at the PetSmart here then it isn't an aquatic plant. Make sure to check the labeling, they sell fully aquatic and "semi-aquatic" plants. Peacock fern is semi aquatic and can be grown near water or partly under but the majority has to remain exposed.
If it's java fern then the care for it and Anubias are similar. They're both low light, don't really need specialty lighting. You don't plant either in the gravel, the rhizome needs to stay exposed so most people tie them to a piece of rock or driftwood.
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