I was wondering why my zz plant is dropping yellow leaves and getting new shoots?! I was gifted it a 3-4 months ago. The first month I think I was overwatering but now I water once a month. It stands about 4 feet tall and is in a drainage pot so I’m assuming there is drainage. It’s in a northeast window. I don’t want to kill it 😳 I also only use my fish tank water……confused