This is a very broad question. You might need a lot of humidity for some Genera, for others with a strong wet dry cycle you might need not so much. I have two glasshouses with no misters but i grow Genera that will survive on lower humidity. Agree with Jane, there is nothing wrong with most tap water. In fact the tap water here is great. I do water with rainwater but that is only because i want to water my orchids at appropriate times, not when allowed by the continuing water restrictions. As for reducing the temperatures. Again, that depends on what you are trying to grow. Just looked at the max/min thermometer at head height in my warm glasshouse. Not reset for several months and it says Min 10C/Max 41.5C . I know a few growers with glasshouses set up with misters and the plants to my eye look too sappy. It all depends on what is in your collection. Ignore the above if you are trying to simulate tropical montane conditions. I'm using a complete fertilizer with trace elements to make for the lack of minerals in water from my rainwater tank.

Fortunately, we're a little less than an inch behind our normal rainfall here. And I seem to be situated in a narrow "weather belt" where if there's a rain producing cloud going over, I'll get it. It can be bone dry a few blocks in any direction. The downside is that it works the same for snow - in an event I can get 2 feet whereas others get a dusting. With Lake Superior as our greatest resource, we rarely have water restrictions. However, the hint is always there to practice conservation, if for no other reason than it's the right thing to do and because all of the lakes are below their normal levels. I know there's an ongoing attempt by thirsty areas west of the Mississippi to construct pipelines and drain off Great Lakes water. Luckily, Canada has a vested interest in this not happening too. Perhaps in the more arid regions, there should be a moratorium on swimming pools? More education on the use of native plants?Well, end of rant. Gardening should be a joyful exercise and I feel for those of you suffering with the angst of watering woes.

It is so nice and useful to read all the information and experiences of our forum members here. I never thought seriously about the water I use for germination, normally I used tap water. Once I used distilled water for spray the plants because the tap water spray make the leaves so ugly. When the water dried all the leaves have whitish residues from the water probably the lime/chalk. When the tap water is dried always chalk/lime built up on the surface. So we have vinegar plus solution for regular cleaning. One of my friends apartment's tap water is pretty bad when he boils it the water lost its color, it looks like water with milk. I hate this chalky water. However, I do not know this hard water is good for the plant. Caelian

Some valve bodies have an auto shut off feature which is designed to prevent scalding. If one side has no pressure, both sides are shut off inside the valve body. Or you dislodged some huge chunk of rust and it made its way to the shower valve. I can't see from here. Try dissembling the shower valve and flushing it out.