My lemon button fern has been in the same container for about half a year. I have it in a fishbowl type glass terrarium along with a few other plants. As I understand it, lemon button ferns don't get very big, which is true with mine, it hasn't grown much at all over the past 6 months. But recently the plant has been looking pretty sad. A lot of the fronds have turned brown, mostly at the base. The plant is still sending up new fiddleheads, but a lot of the fiddleheads turn brown before they can fully grow. The soil in my terrarium is always very moist and I mist the fern every once in awhile. According to what I've read, lemon button ferns like very moist environments, so what do you think is going wrong with the plant?