u/B-school-student

I don't know whats wrong with this guy - I repot it about a year ago and its in a ~9in diameter pot right now. It's been thriving for awhile but the last few weeks just lost all its leaves, stopped growing and is barely hanging on anymore. Is it as simple as repotting to something bigger? its not even that big but I am seeing like a very tiny root come through the bottom of the planter. It's on a windowsill getting west facing light and generally has really really enjoyed it. There are lava rocks and drainage holes and I water 1x a week ~1/2 a cup