In speaking with my friend who has a degree in horticulture, he says that TDS isn't unique at all to orchids, and that TDS, EC, and pH are very important for all commercial greenhouses, orchids aside.
Ray> In speaking with scientist at several fertilizer companies, I have Ray> learned that focusing on TDS is pretty much unique to orchid growers, while Ray> just about everyone in any other horticultural segments thinks in terms of Ray> the EC (electrical conductivity) of the nutrient solutions. Ray> Ray> Given the facts that TDS meters are just EC meters with built-in Ray> conversions, and that the ionic makeup of solutions affect the EC, giving Ray> different conductivities for the same true TDS, it is a poorer measurement Ray> in the first place. Ray> Ray> Does anyone have any factual background as to why we focus on TDS? Ray> Ray> I'm not looking for the usual comments about some plants needing very Ray> pure water or anything like that, but instead, some specific basis for TDS Ray> rather than EC. Ray> Ray Barkalow - First Rays Orchids - www.firstrays.com Ray> Plants, Supplies, Books, Artwork, and Lots of Free Info! Ray> . _______________________________________________ the OrchidGuide Digest (OGD) orchids@orchidguide.com http://orchidguide.com/mailman/listinfo/orchids_orchidguide.com
