I had a couple phals in bonsai style pumice for awhile. I love the stuff for growing houseplants but I noticed the new phal roots refused to penetrate it and the roots in the pot didn’t really grow much. The phals were happy enough but I wasn’t happy with their performance. Once I switched to bark the root growth exploded in the pot and hasn’t stopped. The clay floor dry product probably isn’t as rough/sharp as the pumice but it’s something to keep an eye on.
---------- Post added at 05:29 PM ---------- Previous post was at 05:27 PM ----------
Hmm... Interesting pumice experience. I've been growing with the floor clay products for a few years now. The one I have going now has more healthy green roots than I can see through, but the watering and drying times are important to keep track of, I've found.