I'm a sick Catt, what do I have?

[Phyrex]

This guy is just not getting better. I thought it would be a matter of time and new growths since the weird brown stuff didn't expand, now the new growth has gotten a black tip even though the rest of the plant pretty much stayed the same. The second oldest p-bulb has yellowed now. The brown areas are not mushy at all they just feel like a normal leaf except for the bumps. I marked the leaves with a marker to see if the brown patches were spreading; they aren't. Does anyone have an idea what's going on here?

EDIT: I always take pictures right after watering. It's on a 4 day watering schedule and it's quite dried out by the 3rd day.