A friend gave me this plant but didn't know what it was. I thought it could be some kind of Sansevieria, but I'm not sure. But the problem is the leaves are getting yellow, and I don't know why. The yellow starts from the top, usually. I already took out the ones that were totally yellow, from top to bottom. Someone told me that could be fungus but I don't know how to proceed... I'm currently watering once every two weeks and it's not under direct sunlight. Does anyone have a clue? Thanks!