Brown leaf tips can be caused by many things including too much fertilizer, not enough water, too much heat or a toxin in the soil. Try to note if the tips are crackly and brown which may indicate drought or heat or soft and brown more likely a sign of toxins (urine or a cocktail poured into a pot, tap water with too many minerals) and then consider what to do next. In many cases  watering deeply to wash toxins from the soil and hydrate plant is the first step. Some plants are just more sensitive than others to environmental damage. Keep growing, Marianne Binetti