If that were my plant, I would flush with maybe 2 gallons of water and some clearex. Hopefully your soil has good drainage properties. At your next watering, give her a mild nute mix, maybe 1/4 strength and hopefully this will be a way to start fresh. Salts build up in our mediums and it's a good idea to leach them every few weeks in order for the roots to have the capacity to use what you're feeding it. Salt buildups are also a sign that you are either feeding too much or not watering with enough water. Generally, you want 10% run off from your pot which insures that the salts you're feeding aren't just getting stuck in the soil but making their way through and possibly rinsing older salts.
