How low will the Temp be?

[S|aO_|aNG]

Juz wondering how many degrees will fans bring down water tempertaures in tanks.
I'm hafing a 2ft tank. with 72watts of light shining on. Its about 28-30 degrees everyday. mostly 30 i guess. How much will the temperature be if i use a Ista fan blowing on it?
Thanks~

[sherchoo]

Wow... it's very difficult to comment such query...... I'm guessing that it may reduce by 1~2 deg C but this depends on many factors.

1. Ambient temperature - If the suroundings is warm, tendencyto cool will be harder
2. Angle of the fan - If blowing directly at the water surface, the cooling effect will be higher. Also this will effect your water evaporation rate too.
3. Space between the light - more space would enable cool air exchange
4. Fan size - Bigger fan, higher blowing power (most of the time)
5. Type of fan - DC and AC has different blowing capacity
6. Surface area - surface area is directly proportional to heat exchange rate

errrr... that all I can think now.

[tawauboy]

the humidity level of the surrounding air plays a big part also.

don't think you will have any problem getting 28 deg for a normal day. for rainy days, you may be able to get 26-27 deg.

[budak]

for me, after I added a 4 fan AC unit (from Nature) to my 3 ft with 36Wx4 PL lights, the temp has fallen from 30+C to 26-27C, with marked growth improvement, esp for ferns and mosses. I added a 2 fan AC unit to my 2 ft (36Wx2 PL) and it seems to be helping as well.

[joe]

I use 2 x 80mm fans blowing direct on the water surface. Managed to achieve 27 degrees almost most of the time. A few nights back when night was cooler, the temp dropped to 26 degrees!

[Simon]

i guess u wouldnt have problems lowering it to 26-27.. but be warn of the evaporation rate

[S|aO_|aNG]

Wow~ Thanks~!
I'm wondering now if the Fan from Nature will be better than the Ista ones a not. Cuz i saw tat ther are 2 type of fan there. 1 of them is the Ista fan. & the other is dunno wat brand. But the appearance is MUCH better looking & MUCH lighter than the Ista one. It has 2 small fans inside the frame of i guess around 15cm??? Aga Aga oni lah. Of course it cost $15 more than the Ista one lah. AC or DC i dun noe...
So u all think the Ista one is better or the 'unknown' one is better???

[M0rph3us]

the unknown brand is actually oceanfree...
if u want the look.. get the oceanfree one..
if not i will recommend the ista one cause i feel its more powerful but not appealing to the eyes

[PeterGwee]

Might want to try your luck at Sim Lim Tower...heard from one post previously that one of the shop there allow you to test the fan for its noise level...efficiency like-wise.. hard to say but bigger AC fan is better.[]

[sherchoo]

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On 1/26/2003 4:27:26 PM

AC or DC i dun noe...

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I'm quite sure it's AC. The fan is plugged directly to the socket outlet rite?

[geoffrey]

While we are at temp, has anyone experiences significance negative effects with temp between 29-31 deg Cel? Mine hitted 30 yesterday and this morning it's still at 30. Usually, it's 27~28 and I have not been in this hobby long enough to know what are the effects.

[peterkoh]

kewl. that's a big reduction in the temp. budak. is it noisy with have 4 ac fans ?

i'm using a single DC fan and the most, it reduces the temp by 1 deg. but becoz of the high evaporation rate, I've turned it off a few weeks ago. the temp yesterday was 31.5 !!

does anyone observe the adverse effect of high humidity in the room when using fans ? I'm worries for my walls, furnitures and false ceiling.

thks.

[vinz]

I've tested a few at the shops, and for the 80cm and 90cm sq 12V DC fans, ampherage of 0.22A and below are quiet enough for me.

There's a link to an article about DIYing DC cooling fans in the Aquatic FAQ forum, if you want to give DIY a try.

[vinz]

Geoff, 2 of my tanks are at 30+ degrees. Haven't set up the fans yet. Some plants still live, but some won't.

My 6 ft, at 27-28 celcius, give me less problems then the 30+ degree tanks. Though the fact that it is only a few months old and that it has 4 times the water volume may be factors as well.

[geoffrey]

Thanks Vinz. I have big concern now, anticipating temp to go up the next few days. With my fans running, my temp is still high. Got to check why they are not working effectively.

[chia2k]

try putting the fan close to the water . i use 4 12 v AC fan and it brings my tank temp to 27-26 C.

[kc]

Just to add. Will the type of filter used affect the tank temp? My logic is that since the motor is inside the water, it will surely added a few degree to it.

[geoffrey]

Chia2k: I can't. Given the low clearance I have for my lights, the gap simply isn't enough for me to manipulate the placing of my fans. I am trying to work out a solution to elevate my lights to at least 6" higher from the tank's top edges. To date, I have not come with any feasible and viable solution. Damn Ocean Free lights and its stand are simply too short! And my 2 set of lights completely covers the 2.5 by 15" top of my tank like a hood, not much opening.

[PeterGwee]

Running the fan 24 hrs a day do help to keep the temperature constantly low as compared to switching the fan "on" "off" along with the lighting period. I found that once I "off" the fan after the lighting period, the temperature do rise a bit even though it is night time already. Try both methods to see which one suits you. For me, its running non-stop till it burns out..

[geoffrey]

Peter: I have my fans on and off alternatively for every half an hour during the lighting period. That has help bring temp to 27~28 deg C during the cooler months. Looks like I may have to have it on longer now.