PC fan as exhaust, which end should inbound?

[ninad]

Might be very easy question but I am usng small PC fan as ventilator in my orchid humidity dome which end of FAN should be going inside dome
-- the one which pushing air at you ( currently putting this end in)
-- the one end which removes air

[Arizona Jeanie]

Hi, I'll start out by telling you that I'm not a terrarium expert at all, but I see no one has answered you so here's my opinion! The purpose of having a fan is to circulate air around the plants, this helps prevent mold and general rot with the higher humidity inside the enclosure. Most pictures of terrarium set-ups I've seen show the small fan mounted inside to just create a little breezy air movement inside the terrarium. If you set it to exhaust the air, you'll just be removing the humidity you're trying to maintain. If you turn it to blow air in, that air has to go somewhere, and again you'll be blowing out the humidity. If you look at some terrarium pictures, you'll see most have the little fan mounted up in the corner inside, circulating the humid air that mainly stays inside. Maybe someone who has this sort of arrangement could post a picture for you? I think that one of the problems with very small enclosures is that the lack of air movement inside the dome sets you up for mold and other diseases on the plants. Even though they like the humidity initially, they don't stay healthy. I'm a firm believer in trying to establish the best conditions for my plants to thrive, sometimes it takes some trial and error to get there! Good luck with it, can you post a picture?

[ninad]

Thank you Janie

I created opening in my humidity tray and install fit my PC fan, so when fan start it put air in and from other opening in my humidity dome, inside air thrown out.
I have timer which start this every 15min per hour, so humidity get drop from 95-99% to 70-72%.
This dome is holding my deflasked cattleya babies and some other baby orchids

[Arizona Jeanie]

Hello ninad! The picture helps a lot in understanding your set-up. I so admire people who are propagating orchids, I struggle just to learn how to keep a few Phals healthy on my Arizona windowsill!
I think you might get more response to your questions if you try either the propagation or terrarium forums. I think that in managing your babies from de-flasking to independent living it would be beneficial to discuss the process with those WAY more expert than I am. Carry on!