Trace elements are useful in such tiny amounts that they are often available even when you think they wouldn't be.
Absolutely that is why you got to add 60% perlite 20% vermiculite 20% fluval Stratum and 10% sand. I had given away my recipe many times. My cephs are many years old and I just feed them frog bites one a month or 1 every 2 months. I change medium once every 6 or 7 years.I think there's still a concern with a carnivorous plant missing out on some trace nutrient. For example, if you plant in pure perlite would this plant eventually end up with a boron deficiency? Such a deficiency wouldn't really be noticeable until one day the crown just dies, but isn't something you get from insects as far as I know.
In the wild don't cephs grow on a rocky cliff beside the ocean? I'm imagining there'd be some salt spray from the ocean, and possibly a lot of trace minerals in the clay and ocean spray.