Sounds like over watering. Is the soil fast draining? Does the pot have good drainage holes in the bottom?

Yes it has good drainage, and wasn't overwatered. I was actually watering it with a terracotta spike and wine bottle, so if anything I think I was underwatering and heard from another forum that tropical plants prefer a deep watering and then to dry out. Someone else had said it could be salt injury due to the fact that I hadn't prewashed my top dressing of gravel, When I removed the gravel and hosed it down, it did definitely seem to be covered in a lot of some sort of residue. I flushed the plant with water to get rid of remaining salt, and am going to try some Gypsum to help it recover from the previous damage.

Hope it works!

Build up of mineral salts can be a big problem, especially if you are using tap water. In some areas tap water has a lot of additives. The water that isn't used by the plant evaporates leaving the additives/minerals to build up in the soil. Flushing gets rid of that, providing the water drains off fast. Although, I'm not sure what benefit gypsum would give. One of its main uses is to break up heavy clay soils, usually in garden situations. Another use is to add calcium to the soil without raising the pH, which would happen if lime or dolomite was used.