Den Micro Chip leaf tips turning white

[jam]

Hi, my name is Annette and I am new to your forum. I am a novice when it comes to growing orchids, but they are my plant of choice. I don't have many, but one of my newest, Den Micro Chip has white, drying leaf tips. I have been told that I am possibly overwatering. Media is pumice, possibly perlite and charcoal. I have to admit that I have been watering every other day because some of the canes seem to be a bit shriveled. Any ideas would be greatly appreciated. I don't want to further damage this wonderfully fragrant, attractive plant.