Leca is a porous clay product know as hydroton and several other products.
Being that your not to far from me... Your water quality is about the same. RO filter was the best thing I have done so far.... I have noticed at humidity has made a huge improvement.
Hi keith, are you a member of San Diego Orchid club? Where do you live in SD? I'm in Oceanside by the pier. Hope you can make it to my club some time. Palomar Orchid Club in Carlsbad. We meet on the first teusday of the month.