Best available alternative to PrimeAgra leca

[Ray]

OK, here's the scoop:

There are dozens of different types of LECA available globally. Each has its own set of properties, and some may work better for you than others, but plants will grow in any of them. Experiment!

Also, there was a series of changes in ownership, but PrimeAgra was ultimately manufactured by ATAMI, and they packaged it as PrimeAgra for me. Their brand name for the stuff is Grow-Rokz, and to the best of my knowledge, the stuff sold by Tom at theorchidhouse.org is that.