If any of you have pictures or a good description of what over fertilization or fertilizer burn looks like - especially in phals, I'd really appreciate it if you'd share.
In many plants, especially those with thin leaves, it is usually the leaf tips that start browning. The edges of phal's leaves can do something similar, but you will also see the aerial roots becoming desiccated and stop growing.
However, there are other reasons plants can display such symptoms, so what makes you be concerned about fertilizer burn?