[kenji226]

I plan on using a backpack air circulation set up like this:

http://www.dendroboard.com/forum/pa...osed-air-circulation-system-you-can-make.html

I am going to be drilling the back of the tank and having the intake and output coming through the background. My question is about placement. I see four possible options: Intake and output both near the top horizontally; both near the bottom horizontally; intake near the top, output near the bottom diagonally; and intake near the bottom, output near the top diagonally. Which if any would be best for internal air circulation and keeping the glass clear of condensation?

 

[xm41907]

Check out my post for air circulation. I made something similar but less complicated. It worked well for a few years before I had to dismantle my setup.

http://www.dendroboard.com/forum/parts-construction/28682-recirculation-fan-construction.html

 

[xm41907]

As for placement of the intake vs output, it would depend on your setup and what you'd like to achieve. With mine, both (actually all three as I had a single intake and two outputs. The problem I had with mine was that everything was along the top. I tried to make it a double loop system but I'm sure the air at the bottom of the tank wasn't getting circulated as well as I'd liked. Also my fans were small, probably the smallest you can get. The did not have a strong pull. I'm in the process of designing a plywood setup and intend on doing this again with two systems, one on each side with intake at the bottom and output at the top, or vice versa. Not sure which would be better for airflow. I am planning to create a large rock wall divider in the middle, so the tank will essentially be two separate habitats with small openings between them.

 

[GRIMM]

For best possible condensation removal, output at the bottom, intake at the top. I have found the intake at the bottom to be fine though as it clear most of the glass. Output at the top probably replicates the natural conditions a little better also.

Condensation is more dependant on the temps outside the tank however. Even though you have plenty of in tank air circulation, a cold house and hot tank will result in condensation no matter what. Just the small fact that my house air conditioning duct points near one side of the tank it becomes full of condensation, while the other side stays perfectly clear.

 

[kenji226]

The tank is going in my office, and my office stays pretty cold, especially in the winter. I guess I'll go with output at the bottom, intake at the top like Grimm suggested. The fan I am using is rated at 26 CFM, so there should be a pretty good amount of air flow. It would be a shame to spend all this time on the tank, and no one be able to see in it.