I found a misting system from MistKing that sprays a very fine 50 micron mist. I needed as fine a mist as possible, so that as little water as possible collects at the bottom of the orchidarium. The water in my area is hard and will clog the sprayers, so I decided to get a reverse osmosis system. Water from reverse osmosis is slightly acidic which is like rain water; perfect for orchids. Orchids do not like mineral build up on their roots, so reverse osmosis will get rid of all those minerals. These orchids are so picky, I’m buying them their own reverse osmosis system!?! I will be careful not to mention Kona Deep ($28/bottle) when I am anywhere near my orchids.
There are three valves at the top controlling which supply of water/fertilizer to use. The valve close to the pump is for a ZipDrip system. I put the whole thing inside a box, which is a bit larger than needed (in retrospect I would use a much smaller box).
Here is where I had a major decision to make: attach the orchidarium directly to a reverse osmosis system, or opt for a self-contained system that can easily stand in a living room or entry way without any plumbing hookup. I chose the latter, by putting buckets inside the cabinet.
Three five gallon buckets plus lids just barely fit inside the cabinet. Two are for a weak solution of Green Jungle Orchid Food. I have been using 1 oz. for five gallons. I spray twice per day for four minutes each, since the roots are exposed with no potting medium.
The last bucket is for the SuperThrive vitamin and hormone supplement to promote root growth. I am still experimenting with the amount to use, but am starting with a very weak solution of 1/4 tsp for five gallons sprayed once every two weeks.
I didn’t want to keep looking inside the bucket to see how much water was left, so I mounted an HC-SR04 sonic sensor onto the lid. A pulse is sent to the sensor and the time it takes to bounce back from the surface of the water is used to measure distance.
Here is a video of the sprayers in operation just to give an idea of what the mist looks like, how the sprayers are mounted, the water collecting at the bottom and a view of the main fan in operation. The fan should really be off if the temperature of the water is cold.
I find that after spraying for four minutes when the outside temperature is very cold will result in the temperature inside going down drastically. I am now considering using aquarium heaters, one inside each bucket, to keep the water at a milder 70 degrees fahrenheit.
I will show how to control the sprayers in a later post, but the valves and pumps run off a 24VDC power supply, so four relays are used, one for each bucket valve, and the ZipDrip valve driven off the same relay as the pump.