# No air in?



## trunda (Oct 15, 2007)

Is it possible to make a viv that would be totaly enclosed? Like there would be no outside/inside air comunication, only a fan inside to make the air moving? Will plants produce enough oxygen for the frogs? Is it ok to let the only fresh air in once a day during feeding? Thank you for your opinions


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## defaced (May 23, 2005)

Many people's setups have minimal air exchange. All of my 10gs have a solid glass top that is only opened once every few days for feeding/misting. Some will argue that it's not the best setup, but I've yet to have any problems from it.


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## Rich Frye (Nov 25, 2007)

I have a few vivs with zero vents. No fan either. The pums like very humid warm air. Bad for the (some)plants . Good for the pums. Opening only a couple times a week is more than enough air to breath for them as long as the tank is 'healthy'.
I alway find it interesting when I get frogs shipped to me with holes punched in the deli cups for air when we are trying to insulate against outside temps when shipping. 



Rich


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## bbrock (May 20, 2004)

Fairly sealed vivs with internal air circulation is actually my favorite design after much experimentation. Air movement solves a lot of problems with stagnant air and toxic CO2 accumulation but exchange with outside air is less important. I don't think I would make a vivarium completlely air tight. But my best viv only gets whatever air leaks around the sliding doors (no vent holes at all in the viv) and there is a powerful fan that creates a breeze with internaly circulated air.


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## Rich Frye (Nov 25, 2007)

Another thing to consider is there are thermals created in many vivs for air movement.


Rich


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## bbrock (May 20, 2004)

Rich Frye said:


> Another thing to consider is there are thermals created in many vivs for air movement.
> 
> 
> Rich


Good point, but that's actually not the type of movement I'm talking about. I'm talking about movement that creates a visible breeze. That type of movement breaks up the boundary layer around plant leaves (the reason some plants do poorly in a tightly sealed vivarium) which improves growth. It also prevents heavy gases like CO2 from setlling in low spots which can asphyxiate frogs. And I can't help but think it reduces the petri dish like environment for bacterial growth. 

I do know from experience that a healthy viv without air movement smells good, but a healthy viv with air circulation smells much better. It really does smell like a fresh forest. I'm not saying that I think air movement is necessary for a healthy viv. Most of my vivs are typical vivs that are pretty tightly sealed and no movement. But after many years of experimenting, I sure like the environments and results in vivs with a breeze much more and am working toward moving to all custom vivs that incorporate internal air circulation.


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## nightlifecc (Mar 13, 2007)

If you don't mind sharing, how are you setting your tanks up Brent? I've seen several threads on internal circulation in tanks but I don't believe I've seen your solution.

Are you using the standard computer fan? I've had trouble finding ways of hiding them to keep things looking natural when I'm not forcing air in from the lid (which I didn't like).


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## bbrock (May 20, 2004)

nightlifecc said:


> If you don't mind sharing, how are you setting your tanks up Brent? I've seen several threads on internal circulation in tanks but I don't believe I've seen your solution.
> 
> Are you using the standard computer fan? I've had trouble finding ways of hiding them to keep things looking natural when I'm not forcing air in from the lid (which I didn't like).


Certainly. I actually thought I had posted pics of the arrangement but can't find them, so here is what I posted on frognet:

The intake/exhaust gangs. One on the left is capped because I need to get more duct. The other unconnected vent is for a feeding port.









The collector - 6" duct










The fan - mounted in a 6" stove pipe coupler with great stuff foam










And a bad shot of two of the inhabitants - mom and kid










I actually have plans to improve the ductwork to clean up the appearance and reduce noise of air running through the ducts.


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## nightlifecc (Mar 13, 2007)

Nice setup and Pumilio! I think I'll try something similar on one of my 75 gallon tanks. I don't want to mess with drilling holes in the glass but pictures of your setup gave me some ideas for a way I could implement something similar to what you have done through the lid. I've got a back wall of Creeping Fig which gives me an extremely large area I could use for hose concealment.

Do you have problems with this setup? Water accumulation in the ductwork immediately came to my mind. I don't see a reservoir for runoff so maybe it's not as big of a concern as I expect.

Thank you very much for sharing!


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## sports_doc (Nov 15, 2004)

Brent
I recall seeing your pics in the past, so they must be buried in some thread someplace on here...

Anyway,
2 thoughts:
the first is air movt noise. Wouldnt polyurethane tubing cut down on air turbulence, compared with the braided hose you use now? I think you can get in 1.25" diam, maybe larger.

the other is a product I used in ductwork in past myself. An inline fan made specifically for ductwork. There are LOTS of more expensive versions but this worked fine for me.
http://www.iaqsource.com/product.php/suncourt/db204p/?product=111114&category=1251

I would love to see other systems folks use to move air inside a viv WITHOUT needing to drill. 

Shawn


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## bbrock (May 20, 2004)

Condensation/moisture has not been a problem. There is so much air movement that it really isn't an issue.

Shawn, yes, smooth walled ducting would reduce noise. I should say that the noise from this is barely noticeable outside the viv, and still more quiet than your average greenhouse inside the viv. But my objective is complete silence whether it is possible to achieve or not. 1.25" ID would be too small for my application though as I'm connecting to 2" PVC fittings for the vents. The objective is high volume, low velocity to maximize air movement and minimize noise. My plan is actually to get rid of all the small ducting on the back and just box in two gangs of three vents with acrylic to make an intake and exhaust side which should eliminate all duct related sound.

I think those inline duct fans would be a good solution. I looked at those and don't remember why I decided to build my own. Most likely it was because of the decibal ratings but don't remember. The best that I found were actually radial fans designed for inline duct work to vent radon from beneath house slabs. Very powerful, and VERY quiet, but pretty expensive.

For smaller, or no drill applications, the idea can be scaled down using pvc pipe to route the air circuit under a false bottom or through a hood. The fan can really go anywhere in the circuit and could just be mounted over an outlet for a one intake, one exhaust vent system. To be honest, I actually got the idea after visiting the Biosphere. They have large blowers at the center of the building with air returns at the perimeter which duct air back to the central blowers underground. Thus, they also provide a cooling effect.


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## nightlifecc (Mar 13, 2007)

sports_doc said:


> the other is a product I used in ductwork in past myself. An inline fan made specifically for ductwork. There are LOTS of more expensive versions but this worked fine for me.
> http://www.iaqsource.com/product.php/suncourt/db204p/?product=111114&category=1251


Good idea Shawn, thanks. That looks like the perfect solution for what we're trying here but reading through the manufacturer's FAQ I found this:
*Can I use the Inductor to vent outside air?
The Inductor has to be protected from rain and excessive moisture.*

I kind of expected to come across a warning like that since their normal application would be to transport dryer air. Presumably, our environment would qualify as "excessive moisture" but it sounds like you've had success with this product. How long have you used this product for vivarium ventilation? Mainly, I don't want to buy a duct fan only to have it fail within the first few weeks.

Thanks guys for sharing your experiences!


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## bbrock (May 20, 2004)

Of course it will depend on the setup, but in my app, I wouldn't worry about those inline fans. The air I'm moving is humid, but as I said, I haven't seen any condensation in the ducting. And I haven't seen any signs of rust on the stove pipe section which is completely unprotected from moisture and stove pipe is notorious for rusting when exposed to damp conditions (the inline fan that Shawn posted is in a galvanized fitting). In fact, one of the purposes of the circulation is to dry things out in the viv so it remains humid, but not wet. Much better for orchids and probably frogs too. I would guess that any fan used in these humid conditions would probably crap out a little sooner than if they were operated in dry environments, but still should provide a good service life. But if you really wanted to get something bombproof, you could look into greenhouse fans, or those radon fans I mentioned before. But you will pay a price for them. My only wish is that my fan moved about 50% more air than it does. It makes a gentle breeze you can see inside the viv, but I'd like a little more.


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## nightlifecc (Mar 13, 2007)

Thanks Brent. I've been checking into the radon fans and just as you describe, they look about perfect but at around $130/fan you could buy 5 of the ones that Shawn referenced. Looks like you've done my research for me, thanks. I'm going to stop by Home Depot today to see what they have in the way of duct fans.

I'll be using my 75 gallon leuc tank for the first experiment. If it works out well, I have four 20 gallon tanks that all need about the same humidity levels. To make it cost effective, I'm toying with the idea of getting one large fan and splitting it enough times to have one inlet and one outlet for each. From your experiences it sounds like I may not be able to get much movement in doing this but as long as I can get some air exchange I'd be pretty happy.


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## bbrock (May 20, 2004)

nightlifecc said:


> To make it cost effective, I'm toying with the idea of getting one large fan and splitting it enough times to have one inlet and one outlet for each. From your experiences it sounds like I may not be able to get much movement in doing this but as long as I can get some air exchange I'd be pretty happy.


We are thinking alike! The technical complications go up an order of magnitude when you start thinking about ganging air systems together though. The first issue is that you don't want to share the air between vivaria unless you want an epidemic disease to wipe out your entire collection. So rather than a closed loop, you need an open one where fresh air goes into the vivs, and exhaust air is carried away from all of the vivs and discarded. But an open loop system means that you will likely have to condition the air before it enters the vivs. In my climate, that means it would need to be pre-humidified or else my vivs would all drop to about 35% humidity. But it is possible to rig a trash can or similar as a humidifier that the fresh air would run through before entering the vivs. As long as you maintained positive air pressure, there should be no issues of air moving from one viv into another. For the fan, you would likely need to step up to a radial (squirrel cage) type fan or blower to get the volume of air needed to service multiple vivs. And if you REALLY wanted to go overboard, you could do like thought about. Which is to run an air loop outside the house to a buried air-to-air heat exchanger that would cool the air and use dampers and servos to mix warm and cool air to adjust the temperature of air entering the vivs for temperature control. In my case though, I've pretty much determined I can get plenty of cooling capacity with slight modifications to my lighting systems which is obviously much simpler. But we should never underestimate our ability to overcomplicate our vivaria if we put our minds to it!


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## Dancing frogs (Feb 20, 2004)

As far as reducing the noise with the tubed ventilation system, do you know where the noise is coming from? The fan obviously, but is there resonance causing amplification? 

Some thoughts:

Smooth tubing
Isolate fan vibrations, you could build of possibly buy a flange that would isolate the vibrations to the fan frame, instead of transmitting it to the tube walls.
I also wondered if aeroport ends on the hoses would help, and would they help enough to bother with.
For those that don't know, this is an aeroport (they are designed for loudspeakers, to reduce turbulence at the port, reducing distortion).










My money would be on the previous recomendations though, especially isolating the fan vibrations.
You could also fabricate a box to enclose all the tubing on the back, would improve the looks, and keep some noise in.


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## bbrock (May 20, 2004)

Dancing frogs said:


> As far as reducing the noise with the tubed ventilation system, do you know where the noise is coming from? The fan obviously, but is there resonance causing amplification?


In my case, the sound is almost completely from the corregated duct creating turbulence inside the ducts. The fan itself is whisper quiet when operating alone. And it is suspended by chains and connected via flexible duct to isolate any vibration that could transfer to the vivarium case. The sound produced is not noticeable by most people but I'm picky. It is actually much quieter than the sound of air exiting from a typical force air heating or air conditioning system in a house. But I find those incredibly annoying too. I do think you are right that smooth walled ducts to reduce turbulence, and perhaps some sort of muffler device would reduce the sound from this even further. If the fan weren't already isolate, that would be the first place to start like you say.


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## nightlifecc (Mar 13, 2007)

Have you put much thought into how to build a large humidifier Brent?

The easiest method I could dream up would use a large sealed trash can about half-full of water. I'd drill enough holes in the trash can lid to run air stones down into the base and exhaust tubes which would run to the tanks. Then of course I'd have to vent the exhaust from the tanks outside somehow.

It's a rough idea and there are several variables a person would encounter along the way such as finding the right humidity level. Making sure the trash can and all vivariums are properly sealed could prove to be the toughest (and most important) challenge of all. If there's a leak anywhere in the system, the exhaust won't end up in the intended location which would push the humidity levels in the house up. My dad works in air quality so he likes to remind me of the hazards of mold when he comes over and sees all the air in my tanks at 85% humidity.

I plan to implement a smaller circulation chamber similar to yours on my 75 gallon early next week. As for this project, I'm thinking it is a dream on a distant horizon but it's definitely been fun to discuss.



bbrock said:


> But we should never underestimate our ability to overcomplicate our vivaria if we put our minds to it!


Well said. In our case I think obsession and experimentation, rather than necessity, is the mother of invention.


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## nightlifecc (Mar 13, 2007)

My last post appears to be directed at Brent but I don't want to discourage others from chiming in too. I'm trying to hammer out some ideas I might be looking at sometime in the future so all input is welcome.


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## Rich Frye (Nov 25, 2007)

There seems to be tons of good thought going into air movement. In a large tank where the chosen plants are doing fine (no orchids or the like) and the frogs have a good number of micro-climates to settle into, what could I expect to improve by adding internal air movement not caused by thermals? Breeding being fine. General health monitored and doing fine, ect. I am not and will never be a big plant guy and have found that in my very large pum vivs the amount of air exchanged or moved has much less effect than giving the pums tons of choices as to where to 'hang out'. And making sure that the plants that I choose take hold easily and spread with good root systems. The amount of die-off from leaf decay is no more than that of trickier plants in a viv with good 'plant air' circulation so there is no 'extra' plant decay. I know for a fact that the relative humidity in one corner of a viv will be very different that at another and this gives the frog a choice as to where to hang out. They always seem to end up in the more humid spots. So, I guess my main interest would be in the improvements found with the frogs mating, health, ect. with internal mechanical air movement. 
Brent , your BJ viv seems to have very similar measurements as a couple of my pums vivs. Could you direct me to some pics? I am sure you have posted them somewhere before but I can't remember where. I'd love to compare and contrast. Also if you could give a quick 'what's what' with the basic dimensions and layout, anything not obvious, I would appreciate it. Also, if more than one viv has been involved in the air experiment .
Thanks,
Rich


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## roxrgneiss (Sep 30, 2007)

Hey Shawn and anyone else interested,

I recently installed an internal fan - technically, I had a hole pre-drilled for wires, etc that I used to slip the fan in, but I can see how this could be done by slipping a wire in through a smaller port and making the connections afterward if there were no hole already. 

Here's the fan and adapter I used:










I installed it in about two minutes; easiest thing I've done to this viv. The installation consisted feeding the fan through a wire port and placing the fan in an acrylic rectangle after drilling two small holes for wires. Then inserting the wire hangers (bent at angles and attached to suction cups) and sticking the contraption to the ceiling of the viv. Last, 1/4" hardware cloth was crimped to the ends of the rectangle. It's not as concealed as I'd like, but it works. Other pics of connectors, etc are in my *gallery*.





















I suppose this could be done more tastefully, but I just wanted something simple. It's also very quiet, but I have it set to run with the lights, so the small noise/vibration it does make won't disturb the frog's sleep. :wink: And it does keep the front viewing area partially free of condensation, even when this small fan is running on the lowest (3v) setting. 4.5v is the other setting that will work, but I don't think much more wind is necessary for a 27gal; 3v is enough to move around nearby ferns. The plant movement is kind of neat too; the viv looks more natural to me now.  

Happy Holidays,
Mike


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## Corpus Callosum (Apr 7, 2007)

Here's a recirculating fan plumbed through the glass top (drilled):


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## flyangler18 (Oct 26, 2007)

Nice fan setup, Michael. I may start experimenting with recirculating systems in a couple of vivs soon. How's it drawing power?


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## Matt Mirabello (Aug 29, 2004)

nightlifecc said:


> My dad works in air quality so he likes to remind me of the hazards of mold when he comes over and sees all the air in my tanks at 85% humidity


In a dart frog tank (or mini ecosystems) I would be far more concerned of the hazards of not having mold.


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## Corpus Callosum (Apr 7, 2007)

flyangler18 said:


> How's it drawing power?


It's wired to a 12vDC power supply, the fan is about 100mA and this specific power supply is rated for 300mA so it is enough for a few.


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## nightlifecc (Mar 13, 2007)

Matt Mirabello said:


> nightlifecc said:
> 
> 
> > My dad works in air quality so he likes to remind me of the hazards of mold when he comes over and sees all the air in my tanks at 85% humidity
> ...


Ya, I figured I'd get razzed about that after I posted it. Poor wording on my part. His concern is mold in the house, not the tanks.


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## nightlifecc (Mar 13, 2007)

I like your solution Michael. It's outside the tank so it doesn't detract from the natural look inside the tank. Plus it's clean looking, relatively inexpensive, and it would be easy to add more inlets/outlets/fans. I'm guessing that the computer fans will be quieter than the duct fans too. Thanks for sharing guys.


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## bbrock (May 20, 2004)

nightlifecc said:


> Have you put much thought into how to build a large humidifier Brent?


The best one I've seen was a trash can with a homemade swamp cooler stuck on top. The trash can was filled with water, then a circular humidifing pad was hund from the top so the bottom was in the water. A small pump recirculated water to keep the pad constantly saturated. A blower fan was mounted in the middle of the humidifier pad. So dry air went into the trash can, was pulle through the pad into the center where the fan was, and then humidfied air blew out. Very efficient. The only hassle would be that minerals are going to build up quickly just as with any humidifier.


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## bbrock (May 20, 2004)

Rich Frye said:


> There seems to be tons of good thought going into air movement. In a large tank where the chosen plants are doing fine (no orchids or the like) and the frogs have a good number of micro-climates to settle into, what could I expect to improve by adding internal air movement not caused by thermals?


I actually doubt you will see much improvement Rich. Although I have to say that just breathing inside my pumilio viv since adding the air recirculating, it just seems like a much healthier environment than before. And it was sweet and healthy smelling without the air, but it is just a much fresher feel. But does it translate to improved production? I can't really say because these pums also have a plethora of choices for habitat choice. But I'll also say that my pums don't hang out in the most humid places. They use the whole thing and spend a lot of time right in front of the air. What has driven me to these ridiculous lenths has actually been a desire to grow orchids in the vivs. But as I've tinkered, I've started adopting a philosophy that a good orchid viv is a good frog viv (there are obvious problems with that generalization but you know what I mean). It didn't start that way. It was all about the plants. 

I will say one thing it might do hypothetically. And that is to create more habitat diversity to support more microfauna diversity. I think that is only going to be realized in large vivs. My rule is that when you start approaching 30-50 gallons of vivarium volume per gram of frog, then you start seeing a lot of cool things happening.



> Brent , your BJ viv seems to have very similar measurements as a couple of my pums vivs. Could you direct me to some pics? I am sure you have posted them somewhere before but I can't remember where. I'd love to compare and contrast. Also if you could give a quick 'what's what' with the basic dimensions and layout, anything not obvious, I would appreciate it. Also, if more than one viv has been involved in the air experiment .
> Thanks,
> Rich


Here are some relatively recent pics on this thread: http://www.dendroboard.com/phpBB2/viewt ... ree#174253

There are some ancient pics (pre air improvements) on my web site http://www.bbrock.frognet.org. And the viv pics in the artificial tree article are the pumilio viv. I've made some recent improvements to the outside appearance of the viv and will try to post some new pics soon. The dimensions of the viv are 36"Wx36"Tx18"D. I've run a much simpler version of internal air similar (but not as fancy) as what Mike posted in my cylindrical ventrimaculatus viv (also on my web site. I just mount CPU fans inside 2" PVC pipe after grinding the corners off so they fit in the pipe, and then glue cross stitche screen over the openings. That viv is small and wet and was pretty musty without the fan.


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## bbrock (May 20, 2004)

nightlifecc said:


> I like your solution Michael. It's outside the tank so it doesn't detract from the natural look inside the tank. Plus it's clean looking, relatively inexpensive, and it would be easy to add more inlets/outlets/fans. I'm guessing that the computer fans will be quieter than the duct fans too. Thanks for sharing guys.


Actually, the smaller the fan, the more noise per air volume moved they make. To reduce noise, you want to move high volume at low velocity. So you want the largest fan you can find running at the slowest speed to still get the desired CFM of air moved. I do like Michaels solution. I thought that was really cool the first time he posted. And it could always be scaled up to larger duct sizes.


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## bbrock (May 20, 2004)

nightlifecc said:


> Matt Mirabello said:
> 
> 
> > nightlifecc said:
> ...


I actually do think that reducing mold is a benefit of air circulation. True, we do want to promote fungus growth in vivs, but we don't want the viv air to be loaded with mold spores. A circulated viv just smells fresher compared with a standard, nice smelling viv.


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## Corpus Callosum (Apr 7, 2007)

You are right Brent, I have made this same unit with a larger fan (which moves more CFM while running at lower RPMs) and it is noticably quieter than the version with the smaller fan that's rated at a higher dBA. Just had to find a larger housing for the fan and it works the same.


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## flyangler18 (Oct 26, 2007)

Michael,

Aside from aesthetics are you seeing a benefit to a top mounted vs. back mounted design?


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## Corpus Callosum (Apr 7, 2007)

I wouldn't imagine there to be any difference other than the direction where the air is moving, but either way I haven't done this on enough vivs to be able to answer that question. Give it a shot and you let me know


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## flyangler18 (Oct 26, 2007)

> Give it a shot and you let me know


Fair enough  Now just need to find the parts and the time!


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## bbrock (May 20, 2004)

Corpus Callosum said:


> You are right Brent, I have made this same unit with a larger fan (which moves more CFM while running at lower RPMs) and it is noticably quieter than the version with the smaller fan that's rated at a higher dBA. Just had to find a larger housing for the fan and it works the same.


Along those lines, someone posted either on another thread on this or on frognet that Silenx fans are the quietest you can buy. I haven't tried them yet but would like to: http://www.silenx.com/index.asp But as I said, my corragated ducting creates more turbulence/noise than the fan.

I will say a couple things about top vs. back/side mounting of vents. Top mounting is more likely to bring heat down from the lights. And back/side mounting allows you to place intake and exhaust vents where you choose and then you can mount orchids and other plants that like a lot of air movement right in front of the vents.


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## Sokretys (Dec 16, 2007)

very informative thread everyone!!

just ordered my silenx fan 2 minutes ago. i ordered a fan speed control yesterday and 40 mm fan that was quite loud. 32 dba. new one...14! 

ive got a 12x12x18 exo terra. a fan may be "overkill" as my buddy calls it. but its all ive got and i want to give it a try...why not right? 

as far as mounting...i was thinking about having 2 air intakes...noth being in the back of the acrylic top. and having 4 outakes. two small one on the sides of the middle of the top. and two large ones in the front of the top. creating a nice cycling breeze.

im not sure really if this will work...what do you all think would be the best bet for a top mounted air circulation system using a 40x40x10mm fan on a 12x12x18 exo terra. 

heres my viv. i added some oakleaf creeping fig to all of the bare spots on the back and elsewhere.
http://i256.photobucket.com/albums/hh16 ... G_0132.jpg
http://i256.photobucket.com/albums/hh16 ... G_0131.jpg


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## MonopolyBag (Jun 3, 2007)

Only thing I am thinking now is if you end up putting that fan inside the viv essentially although in the hood, there will be high moisture and eventually corrode the fan. SO, I am thinking of a way tog et around that.


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## bbrock (May 20, 2004)

MonopolyBag said:


> Only thing I am thinking now is if you end up putting that fan inside the viv essentially although in the hood, there will be high moisture and eventually corrode the fan. SO, I am thinking of a way tog et around that.


It may not be as bad as you think. I've had el cheapo (less than $5) surplus fans run for years inside vivs in extremely damp conditions. The only corrosion I've seen is at the connections to the wire leads. Some silicone or waterproof electricians tape takes care of that. It probably helps to run the fans all the time to avoid condensation on them which could speed corrosion quite a bit. One thing I do is to always get roller bearing fans but I don't know how much that helps.


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