Until I get my new monster terrarium I am temporarily using a glass aquarium that is only 19" high. I am extending the height with a homemade acrylic "box" of sorts that will add 8" to the height. I have a flat sheet of acrylic I will use as a top. All the holes for attachments will be in the acrylic extension sides - nothing in the top. Now to the question...
I just purchased two 3" fans from Coralife 3-1/8" Cooling Fan Kit and they are extremely quiet - much more so than same size PC fan. I am thinking all I need is one fan in the aquarium blowing across the front to reduce fogging and add air movement. Does this sound right? I really don't want to blow air directly on the orchids since I will be housing my Cischweinfias and Haraellas and need the extra moisture around the plants. I plan to just slide the top back to vent the tank and will use this method to get fresh air in and hopefully control mold. Let me know what you think about the fan setup.
I don't do most Dendros or large, "floofy orchids". For me it's minis (like Angraecoides), Masdies, Paphs, and others that crept in somewhere along the line. See my orchid list for complete collection (usually not current.)
That should be enough. Infact, those are the fans that I use. They are deceptively powerful, and do a great job at clearing the front glass.
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All that is gold does not glitter,
Not all those who wander are lost;
The old that is strong does not wither,
Deep roots are not reached by the frost.
-J.R.R. Tolkien, LOTR, Fellowship of the Ring