I'm in the process of building an automation system for a Poison Dart frog Vivarium (basically a big glass box, where the interior is jungle like with moss, waterfalls, little pond, etc etc).
I'm planning on keeping track of the temp and humidity with a DHT22, and then using the arduino to trigger the misting system when the humidity gets too low, and triggering the heat pads for the same event with the temp.
I've got the system basically up and running in prototype format, and have mounted the DHT22 inside a little mounting box
...
My concern though, is that since this will be mounted inside that moist environment, the circuits underneath the mounting are eventually going to fail.
I'm thinking maybe I just get out the silicon caulking, and absolutely slathering the entire board (except for the DHT22, of course) with a thick layer of clear silicon. I'd cover the diode, the resistor.. everything.
I haven't seen that done before, and I'm wondering if there's a reason for it?
my little mounting box is this:
holy crap that's a huge photo. sorry.
corvidael:
holy crap that's a huge photo. sorry.
You can always click on modify and replace it with a suitable sized one.
The thing you want to look up is called a
"conformal coating"
many come in a spray can.
Hi, you only need to place the sensors in the Vivarium, the electronics can be outside.
Tom...... 
corvidael:
I haven't seen that done before, and I'm wondering if there's a reason for it?
my little
I have, on a piece of military equipment.
It makes the equipment impossible to repair.
Go with conformal coating for the board, its very effective if you select the correct one AND apply it correctly.
TomGeorge:
Hi, you only need to place the sensors in the Vivarium, the electronics can be outside.Tom......
Yup, the actual Rpi and Arduino will be mounted in a closet under the tank, I'm using the smartgreenhouse.org kittenboard to connect via cat6 to the small black box which houses the sensor:
It's the diode, resistor and most of the hole-y board I want to seal off from the outside, so that the wiring/soldering that's underneath the board is also kept in a hermetically sealed, dry environment.
I'm looking into the spray, but I think it's going to be difficult to keep it off the DHT22.
corvidael:
[quote
I'm looking into the spray, but I think it's going to be difficult to keep it off the DHT22.
Some conformal coatings can be soldered through.
Spray the board first then just the joints after soldering.