help! I am killing a tree

help! I am killing a tree

Hello - I am renting an apartment from an actor, and they have a small tree as a houseplant. I think I am drowning this tree but I am not sure. I see its leaves curling and my automatic reaction is to water it. The tree sits in a pot with a plastic base. I've frequently seen water rising just to the level of the plastic base - i.e., nearly enough water to overflow out the bottom, but not quite. Tonight the tree's leaves are all curling and it looks very decrepit and sad. I haven't watered it all day. At the base, I can still see some water. Even though I want to water it again, I feel that this is very much a bad idea, as the tree already has water to spare, as far as I can tell. Is it possible or likely that I am drowning the tree? Top of tree: Full view: Just to confuse matters, that smaller "plant" in this second picture, nearer the ground, is actually a fake plant. Also to confuse matters, I've gone away a couple times and forgotten to take care of the plant. I just completely forgot. But during that time, I don't think the plant looked quite as bad as it looks now. I think I've been overwatering it recently and it survived better when I was underwatering it. Anyway, help me out, I'm totally killing this tree. How do I figure out the right amount to water it?
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