Cooling Fans & Green Mandarin – 07/15/08
Hello Crew,
<<Hiya Frank>>
Your info has always helped me out.
<<We are pleased to know this>>
Thanks for a great Site.
<<Quite welcome>>
One question is with placing cooling fans in the canopy of my 125G tank.
<<Okay>>
Currently running metal halides, compact fluorescents, and T-5s. I have 3 clip-on fans that barely fit in the canopy and keep the canopy top open to keep the temp around 76-78 during these summer months.
<<I see>>
I am planning on buying a low-voltage transformer and wiring pc fans to keep it cool, quiet and keep the canopy top down to look good.
<<Ah yes…I use a 12v outdoor-lighting transformer to power some computer fans for this purpose>>
I was wondering if about a dozen or so fans can be supported by a 150watt 12v low-voltage transformer, or will I need a larger watt capacity transformer?
<<That depends on the fans and their consumption requirements, but very likely the 150w transformer will be fine. Figure your transformer has about 12.5 amps of capacity (watts / volts = amps), that means that all the fans will need to “total” less than 12.5 amps in consumption. Most 12v fans will have their power requirement indicated in milliamps (mA), with 1000-milliamps equaling 1-amp. These power ratings are quite variable even among fans of the same size so you will need to look around for fans to suit (try MPJA.com), and be aware those power ratings will probably relate to how much air movement and noise the fan makes. And something I have discovered that may be of interest is “not all” Computer/PC fans will run on a common low-voltage power transformer. I don’t know why, but I have a couple fans that will only power up when I connect them to my lab-style bench top power supply. But luckily, most of the fans I’ve purchased have run just fine on the low-voltage lighting transformers I use around my tank>>
Second question is that I was thinking about getting a Green Mandarin. The specs of my tank are.......I've got a 125G tank with 46G sump. About 70lbs of live rock and a 3-4inch DSB. My tank has been up and running for nearly 9months. I already have a Scooter Blenny that has thrived in the 5 months he's been in there.
<<Mmm…and will be a serious food competitor, and maybe even an aggressor, to the Green Mandarin>>
I understand that Mandarins eat pods and other small organisms that live within the sand and rock. I have a 28G tank that I used for Quarantine, but haven’t bought a fish in months. In that tank, I have a 4inch sand bed and about 3lbs of live rock. There are a ton of organisms including pods in that tank. I will normally scatter food and watch them appear in the daytime to gather food. I know that
Mandarins can completely and possibly go through their food source in my main tank.
<<In short order, yes…compounded already by the presence of the of the Scooter Blenny>>
Would this work..........to rotate about 3-5 small 1-2lbs pieces of live rock from my main tank to the 28G so that the life in the 28G would move/populate to these rocks and feed the mandarin in the live tank?
<<It would help…but it would be much better to plumb this impromptu refugium in to the display system to allow a “constant” influx of food organisms and their progeny>>
I have a super small area in my sump that I use as a Refugium with lots of Chaeto, DSB. But I don’t think it would supply too much if any pods since they would be killed by passing through my pump.
<<This is not the problem many think, most small organisms make it through the pump just fine…and even those that don’t still provide benefit/are consumed. The real issue is the size and the refugiums capacity to support the display…best to add a larger refugium>>
So do you think that my 28G tank would work good as a surrogate Refugium to help a Mandarin?
<<It will help, yes…better so if directly plumbed>>
Thanks you guys/gals
Frank X Meadors
<<Happy to assist. Eric Russell>>

Fans And Wiring And Moisture, Oh My!...Using 12v Computer Fans For Aquarium Applications – 08/01/07
Hey everyone,
<<Hey there, whoever you are!...EricR here>>
Eric Russell had written this in response to someone’s question regarding fans:
*<<In fact I would forgo the IceCap fans altogether and use 12v “computer” fans. You can usually get a 4” fan for five-bucks or less on the NET…and in my experience, they usually outlast the 110v fans (I have a couple that are going on 4-years running 24/7). As for a power source, an 88-watt low-voltage lighting transformer ($30 or less) will run several 4” 12v fans with ease>>*
<<Ah yes, indeed I did...>>
Where do I find a lighting transformer thing, and where would I find out information about wiring it to computer fans??
<<Well...the lighting transformer “thing” can be picked up at any hardware store or home center that sells “outdoor” lighting. If you only want to run a couple fans you may want to consider the smaller plug-in “power converters” you can pick up for a few bucks apiece at an online vendor like MPJA (http://www.mpja.com/products.asp?dept=366). Wiring up the fans is pretty basic as long as your fan only has two leads coming from it. If the fan has more than two leads, you can sometimes obtain “adapter” fittings (often from the same source where you get the fans) to reduce the leads to two, or you can experiment with the wires until you find the right combination. The 12v fans are “directional” in that the current has to travel a certain “direction” through the motor. If the fan doesn’t run or it runs backwards after you hook it up, try reversing the leads. Also, make sure you match your 12v transformer to your 12v fans. If you purchase a transformer intended for outdoor lighting you should have plenty of juice to power a handful of small 12v fans, but if you purchase the smaller “individual” power converters make sure you match (or exceed) the “output” of the transformer to the “current draw” of the fan>>
Also, will computer fans be "moisture resistant" to use in the canopy and stand sections??
<<Longevity will depend much on the quality of the fans themselves. Obtaining fans with ball-bearings as opposed to roller-bearings may increase life...and though I’ve yet to try them, the “levitated” fans that run suspended in a magnetic field may be even better. I have a couple ball-bearing fans mounted under my tank behind “closed doors” with a 55g refugium and 75g sump that have run non-stop for years. I have others mounted atop the tank that need replacement on about a yearly basis. It seems the “humidity” of the stand is less harsh on them than the heat and “dust” encountered above the tank and under the lights>>
I know the aquarium specific brands of fans (like IceCap) say they are fine to use with salt-water applications, but not sure if that is just marketing talk or a real concern!
<<The 12v fans are much safer around “any” water in my opinion and have proven quite efficient/reliable in my experience...and most will be much quieter than the 120v fans, though there is usually some tradeoff in power/air flow>>
Thank you so much!
<<Happy to assist. Eric Russell>>

Cool Tank... You've Got a Fan!  7/10/07
Hello Bob & Crew,
<You would have & Crew today.>
For what it's worth...
<Your 2 cents?>
At the risk of being arrogant enough to think that I might have found something that everyone else hasn't already, (less than six months into this) I wanted to offer this to you first. You can decide if I may actually the last person on the planet to figure this out. I certainly realize that I am not the first but who knows who might be able to use this idea.
<Heehee!>
I was having a great deal of trouble keeping my tank cool in the seasonal heat. I was keeping the entire house air conditioned to a very cool temp just to keep from boiling the fish. The tank would always remain many degrees higher than room temp (yes, I unplugged the heater and checked pump motors etc.) and I was about to take the expensive plunge into a chiller when it hit me.
<The chiller hit you? Bad chiller! Bad!>
I simply took a common household fan (approx 16" dia) and positioned it on an angle so that it would blow across the long front side of my 72gal and one short side at the same time. Problem solved! The tank is now maintaining consistent temps around 77deg without all the swings that accompany the outside temp!
<Excellent! Glad to hear this worked for you!>
I am also saving a pile of money in electricity not having to freeze my whole house and family with the A/C to make sure the Clowns are comfy.
<Honey... Where's the wool sweaters?>
Hey, maybe I am the last to figure this out, but if one person needs this simple idea... then I guess he/she will now hold that title. Just thought I would throw that one out there since I hadn't read it anywhere. I had only read about expensive chillers.
<Fans are often incorporated into many lighting units and some people will run them over the top of the tank or the sump for cooling... but this tends to increase evaporation rates. Your idea is quite good and has been used by others, but is certainly worth mentioning here, especially during these, the glorious (IMO, 95F and humid is fine by me!) "dog days" of summer.>
Thanks for the site.
<On behalf of Bob and the rest of the crew you are quite welcome!>
My fish thank you.
<This is nice to hear! We are happy to make a difference!>
Mike
<Cheers, Mich, who is soaking in the wonderful warm weather!>

Tank Cooling…How/Where to Mount the Fans? – 04/08/07
Most of the answers on the site about MH lighting and heat involve canopies, which I am not using.  It's a bare glass top between the lighting and the water.
<<Mmm, I suggest removing the glass top…will aid/benefit gas exchange, as well as assist cooling through increased evaporation>>
Should be a simpler problem, except that I don't have the fan mounting choices described in your answers.
<<A bit more detail here would better help me to help you>>
Like everyone else, I want to go with fans rather than a chiller.
<<Understandable (lower initial cost/power consumption)
I am ordering a Current USA Outer Orbit 48" fixture with 2x150W HQI MH, 4x54W actinic (or 2x130W - there seems to be a choice), and 18 LEDs.  Of course, it comes with a fan installed.
<<Indeed>>
I intend to suspend it about 10" over the 72 gallon Oceanic bowfront reef aquarium
with fish, anemones, soft corals, SPS, an oyster, crabs, snails, urchins, sponge, and a variety of organisms that pop up out of the live rocks.
<<Have you read through our info re anemone systems/mixing with sessile invertebrates?  Not recommended…>>
The system includes a 25 gallon CPR refugium with skimmer and a 10 gallon sump.  I am concerned about heat, because in the summer my old Current USA Dual Satellite pumped the temperature above 80 F.
<<A “couple” degrees increase here would not be a concern…in my opinion>>
I put several frozen water bottles into the sump, but I had to do this about twice a day.  
<<Yes…often effective but tedious>>
The 4" Icecap heat-sensing fans are an attractive addition to push air in and pull it out, but where and how should I mount them?
<<A couple mounted at either end of the tank to blow across the surface would help (after you remove the glass top), as well as mounting one or two to blow across the surfaces of the refugium and sump.  I don’t know enough about your setup to be specific about mounting options, but if you or someone you know is handy with acrylic it’s fairly easy to create some type of mounting apparatus>>
I'm not certain that sump cooling by fan would suffice, and I don't see how the heat-sensing probes would work there.
<<Honestly mate, I would forgo messing with/paying for any “temperature sensing” apparatus re the fans.  In fact I would forgo the IceCap fans altogether and use 12v “computer” fans.  You can usually get a 4” fans for five-bucks or less on the NET…and in my experience, they usually outlast the 110v fans (I have a couple that are going on 4-years running 24/7). As for a power source, an 88-watt low-voltage lighting transformer ($30 or less) will run several 4” 12v fans with ease>>
The idea of two bare fans mounted somewhere at each end of the tank is not aesthetically appealing.
<<I see>>
Suspending them from the fixture is the only option I've thought of.
Richard C. Rockwell
<<Another option, yes…but will require fashioning some type of fan mount.  The most simple would be a piece of acrylic (or even thin plywood) drilled with a large hole to fit the diameter of the fan and with a “lip” to allow affixing to the light fixture.  Regards, Eric Russell>>

Re: Tank Cooling...How/Where to Mount the Fans? 04/09/07
Thanks for replying so quickly -- on a holiday!
<<Quite welcome>>
I'll read up on anemones and sessile invertebrates, and on removing the glass top and suicidal species.  Great site!
<<Indeed...much information/experience/shared knowledge for the taking/learning.  EricR>>

- Temp Activated Fans -
Hey guys!  I'm not sure who will be reading this but I want you all to know that this site is the best source of information anywhere. <Glad you find it useful.> I own a 90 gallon reef aquarium that I struggle to keep cool during the summer months.  I have taken your advise and purchased muffin fans which do a surprisingly good job of lowering the temp; however, I have seen them lower it by too much as well.  I was wondering, is there any product that monitors the water temp and controls when the fans turn on and off? <I've only seen variable speed fans as yet.> I have noticed that there is a similar setup being used in the world of water-cooled personal computers.  A device called a 'thermistor'  monitors the water temperature and then turns the cooling fan on when it gets too warm and off when it gets cool. <Yeah... too bad they're not up to the saltwater environment.> Is there something out there for us fish guys? <Hmm... well there are combined heater/chiller controllers which aren't exactly cheap... you could use one of these to turn on the fans rather than a chiller, and it would modulate the heater and fans as needed. Otherwise...> If there's not, could you invent one? ( : <Just need some funds for design... perhaps you can provide some investment capital? ;-) >
(I'm currently building a water return manifold like the one that Anthony Calfo designed.)
Thanks for all the help you guys give!
- Chad
<Cheers, J -- >

Cooling fans 6/31/05
Hello this morning.<Good day!>
I have installed a fan in for my reef tank in my cabinet. The question is what direction should the flow be? I'm I supposed to draw cold cold air in or exhaust hot air out?<Fans help keep the tank temperature down in two ways.
The air movement moves heat away from the tank and increases evaporation thereby cooling the tank. If you installed the fan in the cabinet (as opposed to the hood or canopy) and you have a sump or refugium, you might consider aiming the fan at the water in the sump/refugium to speed up evaporation. If you installed a single fan in the hood/canopy, you should probably exhaust the hot air out. If you install two fans in the canopy, you could use one to pull cooler air in and the other to exhaust warm air.>
Thank you
Stephan
<You're welcome - Ted>