I grow orchids in a greenhouse in Napa County. The humidity can go as low as 10% at times during the year. To keep the humidity above 50% I installed two humidifiers and set the controls for between 60 and 70%. That keeps the humidity up but my well water contains lots of silica and it deposits on the orchid leaves. To solve this I installed a reverse osmosis system and have achieved 10 PPM dissolved salts in the water serving the humidifiers. I still get unsightly deposits on the leaves. Any suggestions? How do you keep the humidity up in your greenhouse. Thanks I appreciate your thoughts and expertise.