# Internal Air Circulation for a 65g Peninsula



## Mitch (Jun 18, 2010)

Hello,
I'm starting the build for my 65g Peninsula . I have the tank and I'm currently building the stand, but other than that most of this is still in the planning stage. The main thing I am having trouble with is internal air circulation. I have a few questions pertaining to it...
1) How many/What size computer fans should I be using? Is there a rule of thumb? 
2) How should I place them in the vivarium? Like Grimm's Peninsula setup? Or just mounted to the walls? 
3) How do I power them? I've seen James's video but I'm still left a little confused. If someone could point me to a good thread about making a set up it would be greatly appreciated. 

Any help/advice would be great. Thanks!


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## Mitch (Jun 18, 2010)

Bump... Looking for some help here!


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## pl259 (Feb 27, 2006)

I've not put any active circulation in a viv yet, but I can share some thoughts about it. 
No absolute rules of thumb that I know of.

-I'd use DC fans. Their speed can be controlled easier. Older computer power supplies make good power sources and can usually be had for free. Plenty of fan controllers out there. Old cell phone chargers can work too. You'll have to check the fan and charger ratings.

-I'd mount the fans in a location where they can be replaced. They're generally not designed to operate long, in humid environments. There are fans out there that are, but they're more expensive and a little harder to find.

-If inside the viv, they'll need screens to protect the froggies from the spinning blades of death.

-Test before you build/mount. Most DC fans can run pretty slow and it doesn't take much to get the benefits. For DC motors/fans, speed is directly related to voltage, kinda.

-Some people mount them in a PVC pipe with the ends screened, then hide the whole thing.

Passive circulation is another option to consider. All it takes is a temperature differential. Consider just using a big vent with more misting.

Let us know how you go.


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## Mitch (Jun 18, 2010)

Thanks for the advice Eric. Greatly appreciated. I plan on using this fan for air circulation. I was wondering how many I need, though. They are fairly expensive so I'd only like to purchase 1 or 2 if that will work. 

Also, what can I use to power the fans? I will be plugging them in into an outlet and would like for them to be adjustable. 

Thanks for any more help!


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## Absolutbill (Aug 23, 2011)

If you cover in screen expect a substantial loss of air flow volume!


Sent from my iPad using Tapatalk


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## motydesign (Feb 27, 2011)

mitch i have 14 or so of the these (got them for $3 or so from newegg, sometimes they are cheap, sometimes they are expensive... i dont get it?)









look around the house for these









if you can find one thats has an output: 12v then the mA depends on the fan and fan quantity.


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## kenji226 (Oct 6, 2011)

Check out these threads. I found them useful.

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

http://www.dendroboard.com/forum/contests/71997-diy-video-contest-4.html#post649282


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## Judy S (Aug 29, 2010)

How is a cell charger used...? And how does it "hook up" with a computer fan??? I sure wouldn't want to electrocute any frogs...


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## motydesign (Feb 27, 2011)

its ok im an engineer  no frogs will be harmed in the making of this.









see where it says output:12V 1000mA
that means this will supply 12V up to 1Amp of (1000mA=1A) these fans will specify their mA and you want a supply that is 10% greater than that #. if you have two fans the supply needs to be 10% greater than the sum of the two fans.


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## Absolutbill (Aug 23, 2011)

Also that is a 40 mm fan that is only 1.5 inches. I installed an 120 mm and after I wrapped with one layer of screen the airflow was drastically reduced, I even cut out small sections of the screen to try to help recover some air flow.



Sent from my iPad using Tapatalk


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## Mitch (Jun 18, 2010)

Absolutbill said:


> If you cover in screen expect a substantial loss of air flow volume!
> 
> 
> Sent from my iPad using Tapatalk


I've heard this before. Thanks for the info. 



motydesign said:


> mitch i have 14 or so of the these (got them for $3 or so from newegg, sometimes they are cheap, sometimes they are expensive... i dont get it?)
> 
> look around the house for these
> 
> if you can find one thats has an output: 12v then the mA depends on the fan and fan quantity.


Do you have a link to what fan that is? Also, what is that you posted a picture of? I'm guessing a power source? 



kenji226 said:


> Check out these threads. I found them useful.
> 
> http://www.dendroboard.com/forum/pa...osed-air-circulation-system-you-can-make.html
> 
> http://www.dendroboard.com/forum/contests/71997-diy-video-contest-4.html#post649282


I've seen both of these before and they are helpful. Thanks!



motydesign said:


> its ok im an engineer  no frogs will be harmed in the making of this.
> 
> see where it says output:12V 1000mA
> that means this will supply 12V up to 1Amp of (1000mA=1A) these fans will specify their mA and you want a supply that is 10% greater than that #. if you have two fans the supply needs to be 10% greater than the sum of the two fans.


Sadly, I'm not an engineer, nor do I have any understanding of electronics. A little elaboration would be great. 



Absolutbill said:


> Also that is a 40 mm fan that is only 1.5 inches. I installed an 120 mm and after I wrapped with one layer of screen the airflow was drastically reduced, I even cut out small sections of the screen to try to help recover some air flow.
> 
> 
> 
> Sent from my iPad using Tapatalk


Are you saying that one won't be enough for a 65g tank?


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## motydesign (Feb 27, 2011)

ok mitch, very simple those black boxes are ac to dc converters. so obviously they go into a wall (ac) then the word "output" just means what it is going to convert to and the specifications it can provide. each converter is different and the label will tell you.

so the fan has a similar label it states draw. lets use the above pic
1amp supply 

then say this fan (i dont know the CFM on it, but it had numbers i liked  )
ADDA 40MM-CASE-FAN-2PIN 1.57" x 1.57" (40mm) ADDA Case Fan w/2-Pin Connector (Black), 40MMCASEFAN2PIN @ AntaresPro.com
it requires 12V which the power supply give, the fan needs .05A this means the power supply can give you enough amps for 18 (lets say 15 for safety).

the wiring is very simple, the wire sraight in two wire to two wire(+to +and - to-). if you need a control (potentiometer setup) look at the how to winner last month


honestly most the time they are .2A~


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## james67 (Jun 28, 2008)

watching a movie, but i'll reply with answers to all the questions when its over.

james


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## Absolutbill (Aug 23, 2011)

I am just saying I am disappointed in the air flow I get after I covered my fan in screen and I have a 120mm in a 36x24x18 exoterra. I installed the fan in my tank (froglets are still in quarantine ) without screen wrapping and there was a nice breeze across my broms and all my condensation on the glass was gone. When I wrapped the fan, it was a lot less air flow and the condensation was back!


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## Pumilo (Sep 4, 2010)

Absolutbill said:


> I am just saying I am disappointed in the air flow I get after I covered my fan in screen and I have a 120mm in a 36x24x18 exoterra. I installed the fan in my tank (froglets are still in quarantine ) without screen wrapping and there was a nice breeze across my broms and all my condensation on the glass was gone. When I wrapped the fan, it was a lot less air flow and the condensation was back!
> 
> 
> Sent from my iPad using Tapatalk


Size doesn't matter. It's more about the CFM (cubic feet per minute air flow). There are big 120mm fans that don't move diddly squat and there are 40mm fans strong enough to almost lift themselves like a hovercraft if laid on their face. As a starting point, some of the cheap fans that only move 8 or 9 CFM are going to be more or less useless in a viv. My first fan barely moves the air. It was an eBay cheapy. I then made a batch of about 10 using this fan. 2410ML-04W-B40 - DC Axial Fans - NMB Technologies Corporation I still got a nice deal off of eBay for them. They move 21.5 CFM which I find to work quite nicely for my purposes. It is a 12 volt fan so uses a 12V convertor. Now I wanted simplicity in wiring so I chose to go direct wired to the transformer. It is still adjustable, however, because I got adjustable transformers. This is the type of transformer I got. 20W Digital Universal AC Adapter China (Mainland) Power Supplies 

The transformer is adjustable from 3 to 12 volts. This allows me to turn it down to 9v or 7.5 volt if I want to turn it down to slow down the airflow. Now the amperage on my transformer is rated at 1.8-2 amps (2.2 max) We will look at the lower end for safety and say that it is only rated 1.8 amps. 

The amperage draw on my fans is stated as .17 amps on the spec sheet, but the fan itself says .22 amps. For safety, I will be using the higher amperage and say that these are rated at .22 amps. 

Remember back to Moty saying you need to allow an extra 10% amperage for safety? I like to just subtract that 10% from my transformer's amperage right now. 1.8 Amps - 10% = 1.62 usable amps.
Transformer 1.62 amps
Fans .22 amps each 
1.62 divided by .22 =7.36 That means my choice of transformer will safely power 7 of my fans.


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## james67 (Jun 28, 2008)

Mitch said:


> Hello,
> I'm starting the build for my 65g Peninsula . I have the tank and I'm currently building the stand, but other than that most of this is still in the planning stage. The main thing I am having trouble with is internal air circulation. I have a few questions pertaining to it...
> 1) How many/What size computer fans should I be using? Is there a rule of thumb?
> 2) How should I place them in the vivarium? Like Grimm's Peninsula setup? Or just mounted to the walls?
> ...


the number of fans needed will depend on their placement as well as the volume of air the fan is capable of moving. 

the mounting style is up to you but mounting it in a way that will provide easy acess to the fan in case of failure will be important. this will of course be much easier if the fan is mounted outside of a duct system.

there are a few options for powering your fans.
yes you CAN use old computer power supplies or cell phone chargers but ONLY if the unit can power the fans safely. using an inappropriate power supply is a fire hazard.




Mitch said:


> Thanks for the advice Eric. Greatly appreciated. I plan on using this fan for air circulation. I was wondering how many I need, though. They are fairly expensive so I'd only like to purchase 1 or 2 if that will work.
> 
> Also, what can I use to power the fans? I will be plugging them in into an outlet and would like for them to be adjustable.
> 
> Thanks for any more help!


i do NOT suggest using that fan. it has a low RPM (revolutions per minute) and therefore doesnt move much air. (under 6 cubic feet per minute)

i suggest finding the fans i showed in my video. they are delta FFB0412SHN-R00. they operate @ 12V and push 24 cubic feet of air per minute. one fan will probably work fine, but id suggest 2 fans and i strongly recommend using a fan controller which will allow you to change the amount of air being moved to perfectly suit your viv. you will be hard pressed to find a single channel fan controller that can handle both fans (amperage) so you should look for 2, 3 or 4 channel controllers (even if you only use 2 of the channels, since 2 channel controllers are surprisingly difficult to locate)



Absolutbill said:


> If you cover in screen expect a substantial loss of air flow volume!
> Sent from my iPad using Tapatalk


remember that the screen is rated a few ways, first the mesh. this value indicates how many wires there are in each direction per inch. of course the higher the mesh value, the smaller the openings will be. the next value is the diameter of the wires. meshes of the same values (like, as an example, 80x80) will have different size openings if the width of the wire is different. as the wire diameter increases the holes become smaller. which brings me to the final and most important value. open area. open area is the amount of unrestricted space for air to flow. it goes without saying that the more open space the less loss youll experience in terms of air flow. when you actually figure the open space of screens you might be surprised 50% or less would be a pretty common figure so your cutting the available space for air to flow, by a significant amount. putting one on both sides of the fan will compound this and its not surprising that you saw a huge decrease in the fans abilities. i suggest using screen wich is placed far enough from the fan that instead of protecting frogs fingers you need only to have mesh fine enough to seal the fan from froglets.



Judy S said:


> How is a cell charger used...? And how does it "hook up" with a computer fan??? I sure wouldn't want to electrocute any frogs...


the cable is cut, the wires are stripped and the leads are connected to the fan. i show how to do this properly in my video (using solder and heatshrink)



motydesign said:


> its ok im an engineer  no frogs will be harmed in the making of this.
> 
> 
> 
> ...


to figure the proper power supply requirements look at the fan's specifications. 
voltage is important as this will determine how fast the fan spins. a 12V fan will operate usually from 3-12V and the amount of air moved decreases as the voltage is lowered (like by using a fan controller) do not supply more voltage than the fan is rated for since this can cause the fan to actually break apart and become very dangerous.
next and most importantly look at the amps that the fan draws. your power supply needs to produce a minimum of 10% more amps than the fan will draw. you can supply as many amps as you want (like to allow for more fans to be attached in the future) and the fan will be unaffected. its amperage rating of the fan is what it draws and it will draw that amount regardless of how much is supplied by the power source. (1A = 1000mA) the fans i suggest, for instance, draw .6A or 600mA. i would need to have a power supply capable of supplying 1320mA to draw 2 fans. thats 600mA each plus 60mA each for the 10% extra needed to ensure safety.

james


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## KeroKero (Jun 13, 2004)

Just wanted to throw my 2 cents in... when working with air flow and circulation my main goal is to get the leaves of the plants dry in 2-3 hours after spraying, and especially that they are dry before lights off (since the heat of the lights usually plays a part in their drying off as well so they may not dry off, and water sitting on leaves may end up getting cold and cause damage). Moving humid air can still dry off a plant pretty well without dropping humidity a huge amount!

I learned this the hard way over the years working with some more sensitive plants like orchids, ferns, and gesneriads... if the plant is fuzzy or hairy there will be issues if water sits on them for too long! Rotting out plants is a huge issue in many frog tanks so if you work out the air circulation the right way you'll be able to grow just about anything - and your frogs will be healthier for it too.


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## GRIMM (Jan 18, 2010)

I think everything has been mentioned except one thing.....Decibel rating! Meaning how annoying the fans will be. Im assuming this is a display tank, so Im sure you dont want it making noise all the time.

I had two cheap 40mm fans in my old tanks and they were terrible. In the peninsula I have two high quality 80mm fans that move 4 times the amount of air, and are rated 10db quieter then the 40mm fans. Try and find something rated at no more then 21-23dB and they should be almost silent using a glass top.

Also, I think for a 65 gallon tank you will want an overall airflow around 25-30cfm. I provide my 150 gallon tank with 60cfm 24/7, and its bang on perfect.


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## motydesign (Feb 27, 2011)

grimm you beat me to it!!! the dBa on the fan was something that was important to me as well. the green ones i had pictured is an 11cfm at 26 dba. being these are for 55gal and under i have been happy with 11cfm on a timer that kicks on ever two hours. i do a 10 -15 min interval. if you use that cfm # you will do an air change on a 55 almost 4 times in a minute (this is with out a mesh, so the number is less)
im happy with a solid air change every two hours as any more than that will dry a tank out in utah with our dry relative humidity and gas fire furnaces in the winter


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## Pumilo (Sep 4, 2010)

Found the site I based my fan builds off of. DIY Air Circulation | GlassTropics


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## Mitch (Jun 18, 2010)

Wow, thanks so much for the awesome replies guys! Now it's time to do some more research and buy some fans...


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## pl259 (Feb 27, 2006)

This is a good spot to toss in some more wall wart wisdom. Some are regulated, some are not. The better ones will sometimes say "Reg" on them if they are regulated. Many are regulated but don't say it.

A supply that's rated at 12V, 1000ma, will act differently whether it's regulated or not. A regulated version of this supply will continue to output the 12V when the load is 1000ma or less. An unregulated supply will only output 12V at the rated current, 1000ma. For loads less than 1000ma, the output voltage will actually be higher. 

Just something to keep in mind. It doesn't affect fans all that much, but could make a big difference if powering say an LED. The smaller cell phone wall warts are often unregulated supplies.


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## Mitch (Jun 18, 2010)

pl259 said:


> This is a good spot to toss in some more wall wart wisdom. Some are regulated, some are not. The better ones will sometimes say "Reg" on them if they are regulated. Many are regulated but don't say it.
> 
> A supply that's rated at 12V, 1000ma, will act differently whether it's regulated or not. A regulated version of this supply will continue to output the 12V when the load is 1000ma or less. An unregulated supply will only output 12V at the rated current, 1000ma. For loads less than 1000ma, the output voltage will actually be higher.
> 
> Just something to keep in mind. It doesn't affect fans all that much, but could make a big difference if powering say an LED. The smaller cell phone wall warts are often unregulated supplies.


I think I'm going to stay away from Wall Warts and instead use a variable wattage AC power adapter. I'm planning on getting two of 



 for the two Delta Fans I just ordered. Will that work?

Here's a link to the Delta Fans, for some reason it won't let me put the link above: http://parts.digikey.com/1/parts/2155646-12v-dc-fan-40x40x28-mm-ffb0412shn-r00.html

I should also add that the fans I purchased a 51 Db. But being that they'll be enclosed in a glass box within a duct system and will probably be running at lower levels the noise should not be terrible, hopefully...


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## james67 (Jun 28, 2008)

Mitch said:


> I think I'm going to stay away from Wall Warts and instead use a variable wattage AC power adapter. I'm planning on getting two of these for the two Delta Fans I just ordered. Will that work?
> 
> Here's a link to the Delta Fans, for some reason it won't let me put the link above: 12V DC FAN 40X40X28 MM - FFB0412SHN-R00
> 
> I should also add that the fans I purchased a 51 Db. But being that they'll be enclosed in a glass box within a duct system and will probably be running at lower levels the noise should not be terrible, hopefully...


yes the fans are 51dB running at 13V, but your unlikely to need to run them at that speed. also once the fans have been running you get used to their hum and it becomes like white noise that simply blends into the background. i will say that unmuffled and running full blast they sound like little jet engines.

the link to the power supply doesnt work (and its the voltage you want to adjust not wattage) but i'd personally use a 2A 12V power supply and wire in a controller like this: most ratings supplied only give something like "output current 1A". however you'll need to make sure that it supports at least 660mA PER CHANNEL.
New 2 ports Fan Speed Control baffle For PC Desktop Cheap Prices
i have used this controller with these exact fans and it heats up but works ok. however when i recieved it it was actually a 3 channel. 
High Quality 2 Ways Speed Controller for Fans,Speed Controller for Fans
4 Channel Fan Speed Controller only $6.50 - Fan Control Panel
4 Channel PC Fan Speedd Controller
this looks to be the best option (even if you use only 2 of the 4 channels). its clearly rated to handle the amperage draw AND its enclosed in a nice little case.
3.5 Multi Channel 2 Fan Controller Temperature Monitor w/ VFT Dispaly,3.5 Multi Channel Fan Controller 
this one does not specify how much amps are able to be controlled so it may fail.

james


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## Mitch (Jun 18, 2010)

James, this controller seems like the best option as of now. Do you have any recommendations for a power supply? Links would be appreciated. Thanks!


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## Mitch (Jun 18, 2010)

Turns out all of those fan controllers have to ship from China. Sears carries this one with similar stats. Also, will two of these work as a power supply? Thanks.


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## Pumilo (Sep 4, 2010)

The link you gave for your fans says that they are only .5 amps. You are using only 2 of them, right? Your latest link for a power supply shows 2 amps. That means you could power up to 3 of those fans safely with only one of your power supplies.


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## Mitch (Jun 18, 2010)

Pumilo said:


> The link you gave for your fans says that they are only .5 amps. You are using only 2 of them, right? Your latest link for a power supply shows 2 amps. That means you could power up to 3 of those fans safely with only one of your power supplies.


Oh yea, you're right. I guess I missed that. I'd only need one power supply then, but how would I wire it for both fans?


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## james67 (Jun 28, 2008)

Mitch said:


> Turns out all of those fan controllers have to ship from China. Sears carries this one with similar stats. Also, will two of these work as a power supply? Thanks.


they look similar but the chinese one has an amperage rating of 2.8A and the sears one is 1.5. its not clear on either whether this value is for the enire unit or for each channel, but i have a feeling its likely to be for the entire unit. which means that your better off waiting the 2-3 weeks for delivery from china (ive ordered tons of stuff from china and IME it always arrives more quickly than i would have thought)



Pumilo said:


> The link you gave for your fans says that they are only .5 amps. You are using only 2 of them, right? Your latest link for a power supply shows 2 amps. That means you could power up to 3 of those fans safely with only one of your power supplies.


these used to be rated @ .6A it seems that they now are rated for .5A. even still that means that youd be putting a load of up to 1.1A on the power supply. you may be able to find a 1.5A power supply but ive found its easiest to get units at 1,2,3, etc. 

james


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## Mitch (Jun 18, 2010)

If the fans are going to use 1.1A then why can't I use the 1.5A controller? Also, I'm still confused on what power source to use. If you could give me a link to one so I can see what it is that would be greatly appreciated. Thanks!


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## james67 (Jun 28, 2008)

Mitch said:


> If the fans are going to use 1.1A then why can't I use the 1.5A controller? Also, I'm still confused on what power source to use. If you could give me a link to one so I can see what it is that would be greatly appreciated. Thanks!


i was saying that since you have the choice between 2 4 channel units , i personally would get one that can easily power 4 fans so that if you decide to expand in the future you can use the same controller for 2 more fans rather than buy another unit.

here are a ouple power supply options:
this one will work for 2 fans only (you can not expand unless you replace the power supply)
http://www.amazon.com/12VDC-Power-Adapter-Supply-Camera/dp/B005G1FJ7W
the nice thing is that unlike a wall wart it will occupy only one socket space and allow for other electronics to be used in the same outlet.

this unit will alow for expansion (if the correct controller is selected)
POWER SUPPLY AC ADAPTER 12V DC 2.5A AMP LEADER W/Cord on eBay!
again this is a laptop style so it will not block the adjacent socket

james


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## Mitch (Jun 18, 2010)

james67 said:


> i was saying that since you have the choice between 2 4 channel units , i personally would get one that can easily power 4 fans so that if you decide to expand in the future you can use the same controller for 2 more fans rather than buy another unit.
> 
> here are a ouple power supply options:
> this one will work for 2 fans only (you can not expand unless you replace the power supply)
> ...


Cool, I'll look into those. Once again, thanks so much for your help!


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## Mitch (Jun 18, 2010)

I actually ended up purchasing a different type of fan that's pretty much as powerful and *MUCH* quieter. Once I get the 51 Db fans I'll have to return them. These are the ones Grimm recommended in his video, which are only 18 Db and put out up to 28 CFM. Plus, they're cheaper. So basically they beat the heck out of the Delta Fans... sorry! I also purchased this power source and this wiring. 

Now all I need to get is a controller...


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## Pumilo (Sep 4, 2010)

I think James was trying to hook you up with a smaller, less obtrusive fan. A smaller fan has to turn a LOT more RPMs to put out the same airflow. James linked you to 40mm and now you are looking at an 80mm. The advantage is that it is quieter. The disadvantage is that you can take four of Jame's fans and place them into the same surface area that your new one takes.


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## Mitch (Jun 18, 2010)

Pumilo said:


> I think James was trying to hook you up with a smaller, less obtrusive fan. A smaller fan has to turn a LOT more RPMs to put out the same airflow. James linked you to 40mm and now you are looking at an 80mm. The advantage is that it is quieter. The disadvantage is that you can take four of Jame's fans and place them into the same surface area that your new one takes.


Yea I definitely realize that but being that this tank is right next to my bed I think something much quieter will be better. Hats off to James though for all the help. Well, all of you guys too. You guys are great.


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## james67 (Jun 28, 2008)

its the difference between a 1.5" hole or a 3" hole. which is HUGE. i personally wouldnt use anything over 60mm since you either have a huge eyesore of a fan in the viv or gigantic tubing outside. 

you'll find that the hum of the fans is something that just seems to fade into the background. i use fans for cooling aquariums as well and while its audible i quickly forget that its even there until i think about it.

either way, you'll be happy having the fans and it helps a lot with keeping conditions just right. 

if you need any assistance with wiring etc, im happy to help 

james


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## ritersofly (Oct 23, 2010)

So just so I'm clear, sorry if I'm dumb, if I have a 12v fan it needs atleast 10% more v power from the ac adapter?? so something just over 12v? But then I read if the fan runs higher than its supposed to it can break?? But if I get a 6v ac adapter it wont run? Or will it only run at half its power??? Sorry again...


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## dom (Sep 23, 2007)

this is a good thread filled with some nice links! thanks guys for all the input. I know I wasnt the original poster but some questions of my own were answered! I have a few fans on some of my vivs and like james said then noise soon turns into white noise and you can hardly notice it!

-dom


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## Mitch (Jun 18, 2010)

Pumilo said:


> I think James was trying to hook you up with a smaller, less obtrusive fan. A smaller fan has to turn a LOT more RPMs to put out the same airflow. James linked you to 40mm and now you are looking at an 80mm. The advantage is that it is quieter. The disadvantage is that you can take four of Jame's fans and place them into the same surface area that your new one takes.





james67 said:


> its the difference between a 1.5" hole or a 3" hole. which is HUGE. i personally wouldnt use anything over 60mm since you either have a huge eyesore of a fan in the viv or gigantic tubing outside.
> 
> you'll find that the hum of the fans is something that just seems to fade into the background. i use fans for cooling aquariums as well and while its audible i quickly forget that its even there until i think about it.
> 
> ...


Yup, well it's possible I can test out both types of fans to see which I like better. I think that if I cover it up well enough the 3"x3" duct system for the larger fans should no intrude much with the hard scape.


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## Pumilo (Sep 4, 2010)

ritersofly said:


> So just so I'm clear, sorry if I'm dumb, if I have a 12v fan it needs atleast 10% more v power from the ac adapter?? so something just over 12v? But then I read if the fan runs higher than its supposed to it can break?? But if I get a 6v ac adapter it wont run? Or will it only run at half its power??? Sorry again...


No, it's amperage, not voltage. For a 12 volt, one amp fan you can NOT power it with a 12 volt, one amp power supply. Instead you need a 12 volt 1.1 amp power supply (which is not made so you actually need a 1.5 or 2 amp power supply). You can also use a 6 volt 1.5 or 2 amp power supply and the fan will operate slower. You can NOT go the other way in voltage and try to operate a 12 volt fan with a 24 volt power supply. You could start a fire with too much voltage. James can give the details and whys better than I can.


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## james67 (Jun 28, 2008)

Pumilo said:


> No, it's amperage, not voltage. For a 12 volt, one amp fan you can NOT power it with a 12 volt, one amp power supply. Instead you need a 12 volt 1.1 amp power supply (which is not made so you actually need a 1.5 or 2 amp power supply). You can also use a 6 volt 1.5 or 2 amp power supply and the fan will operate slower. You can NOT go the other way in voltage and try to operate a 12 volt fan with a 24 volt power supply. You could start a fire with too much voltage. James can give the details and whys better than I can.


you gave solid advice doug. but i'll be happy to elaborate...

voltage is the ability to move a charge between to points, but whats important for you is, that voltage will control the rotational speed of the fan, allowing it to push more air (by spinning faster) as voltage increases, and to move less air (by spinning the blades slower) as voltage decreases. most 12V fans will operate between 3 and 12 volts. lower than 3V will generally not supply enough charge to power the fan, and voltage over 12 (or sometimes 13V) will cause the fan to run faster than it is designed to, which could cause overheating of the components or worse, a sudden disintegration of the unit which could throw material out and injure people or animals. 

amperage draw is the amount of current that is consumed by the component. this should remain fairly constant. what is important for you here is that you need to supply the unit with 10% more amperage than it's going to draw so that in the event of a spike you'll be safe. supplying less amperage than needed will cause the power supply to overheat and will very likely lead to a fire.

james


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## J Teezy (Jan 25, 2012)

there is mention of videos on this link. I can't seem to find them. Anyone can link them?


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## james67 (Jun 28, 2008)

james


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## Rasagul (May 25, 2015)

Did Wessley from star trek just teach me how to wire a fan for my frog tank?


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## CTM75 (Aug 10, 2005)

Pumilo said:


> Size doesn't matter.


Sure...keep telling yourself that.


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