Should I get a Reverse Osmosis unit?

[Roberta]

AFid, I think that your water quality is quite adequate for the plants that you have now, the only group in your list that might be a bit picky (and therefore happier with RO) are the Phrags. But if they're growing now, clearly not necessary. (Paphs totally don't care... the Huntington Botanic Garden in southern California has a world-class Paph collection, and they have found that they actually do better with well water ranging from 200-800 ppm TDS, liquid rocks, than they do with RO!) Dens, it depends... most of the larger ones don't care, if you want to tackle Den. cuthbertsonii then you need RO. Many of the higher elevation Dens from Papua-New Guinea need RO If you want to get into the more sensitive little cloud-forest plants, RO would give you better results pretty much across the board. If you try Disa, no question, they need it. Most Catts don't care. But Sophronitis (even if they're now Cattleyas) do need good water. Also, for those baby orchids that you're cultivating, when they get deflasked they will probably do better with pure water. You don't need a very large unit, small plants don't use that much water.