Flexible Internal circulation
You may have seen this FTS featuring a low dBa 120 mm fan in my azureus viv:
I had initially installed a pair of 60mm fans typically used for cooling CPU's, but I could hear these fans and thought they may disturb the frogs. I then picked up a high CFM, low noise 120mm fan and made several modifications:
- cut fiberglass screen to size for both sides of fan
- installed plastic fan guards over the screen which held the screen in place between the guard and the fan blades
- siliconed the fan guard in place
- siliconed 2 magnets to the top of the fan
I ended up with this:
Once the top magnets were in place, I was able to secure the fan to the top of the vivarium using two magnets on the outside of the lid (I'm illustrating the magnets in place on top of the fan sans lid, but I think you'll get the idea):
I was pleased with this approach because it was not permanent and easily movable. I found that initially I was repositioning the fan for the first week or so to get the air movement right. This was fairly easy to do, and if I was careful, I was able to reposition the fan without entering the viv my sliding the externally mounted magnets around...slowly.
After all that, I might not need the circulation fan
After installing this fan I continued to experiment with my lighting, focusing on air circulation through the fixture. I documented the specific Exoterra hood modifications here:
These fan modifications were great at keeping the fixture cool, but it got me thinking - if I open the vents wider at the front and drop the hoods, perhaps I can draw air directly out of the viv pulling fresh air through the lower front vent, eliminating the need for the internal fan. I cut a 4" vent across the front of the viv top:
I saved the piece that was removed and made a 60/40 split, using the 60% length as a means of controlling venting on the left side of the viv. The right side remained open since I am using a repti-sun UV bulb. I can then slide the extra piece around depending on my venting needs, often sliding the piece toward the back of the viv to open a continuous vent across the front about 1" wide.
Here is a view looking up from within the viv:
With this hood layout, I no longer need the internal circulation fan; the front glass remains clear, and my temp and humidity remain steady within expected ranges. Both fans that are installed in the hoods have built in speed controllers - I basically run them on low, minimizing the air movement and noise out of the hood, but it's enough to do the job.