What size fan should i get?

[kuruppa]

Hi, may i know how to estimate what size fan should i get for my tank to achieve a low temp of 24-27 degrees? It's a 1.5ft long tank.

By the way, how are fan sizes measured anyway?

[Burnz]

eh, I DIY-ed using a normal computer fan which is about 9cmx9cm (fan and casing) for my 3 footer. I get a constant 25 deg from it.

[kuruppa]

i see. does it mean that a bigger size fan is able to produce a lower temperature?

by the way, just to check can all fans be mounted on the 5plan type tanks with the black edges?

[williamng]

Bro

Getting 24degC to 25degC with a fan is extremely difficult in my opinion. 26degC sounds more reasonable. However, it really depends on how high is your ambient temperature. If you live at a high floor that is very windy and your tank volume is low (10lites), then I believe 25degC could be possible. If you ask around, in normal conditions, I doubt you will get 26degC.

For those who are able to get 25degC for large tank, I think the fan are big and water top up is very frequent?

[hebi]

for my 3ft using those cpu fan( i think, it has metal casing around it) which my dad bought from sim lim square i think, it managed to maintain the temperature at around 26C, changing occasionally. for the same kind of fan, it manage to cool down my 1ft to 23C and highest 26C. for the dymax fan i bought for easy placement, its much quieter and also much weaker, so my 20cm cube lowest is 26C and normally around 26-27C.

so i think if you want to achieve lower temperature, size may matter, but i think the speed of the fan rotating matters more. correct me if im wrong

[tawauboy]

the main criteria air volume being moved across the water surface.
computer dc fans sizes are based on their dimensions. a 80mm fan has a housing that is 80mm x 80 mm. the fan diameter is about 70mm.
cooling using dc fan is based on evaporative cooling. so achievable temperature reduction is about 2-3 degrees below ambient temperature.

[torque6]

i have success lowering the temp for my 9L from 28-> 25 degrees constant, i am using a DIY 12cm thermaltake 1255, slient with LED. its running on only 4.5v.

[Burnz]

Bro

Getting 24degC to 25degC with a fan is extremely difficult in my opinion. 26degC sounds more reasonable. However, it really depends on how high is your ambient temperature. If you live at a high floor that is very windy and your tank volume is low (10lites), then I believe 25degC could be possible. If you ask around, in normal conditions, I doubt you will get 26degC.

For those who are able to get 25degC for large tank, I think the fan are big and water top up is very frequent?

for my 3ft using those cpu fan( i think, it has metal casing around it) which my dad bought from sim lim square i think, it managed to maintain the temperature at around 26C, changing occasionally. for the same kind of fan, it manage to cool down my 1ft to 23C and highest 26C. for the dymax fan i bought for easy placement, its much quieter and also much weaker, so my 20cm cube lowest is 26C and normally around 26-27C.

so i think if you want to achieve lower temperature, size may matter, but i think the speed of the fan rotating matters more. correct me if im wrong

Ah, to correct myself the temperature would usually range between 25/26 deg with the 90mm x 90mm fan at 12 volts in my room condition. The fan is probably much noiser than off the shelve aquarium fan and there is substantial rate of evaporation in this case.

[williamng]

Well, the disadvantage is you need to top up water very frequently.

[kuruppa]

thanks guys. what about the placement on five plan tanks with the black edges all round the tank? will all the clips fit? cos similar clips from certain clip on lights don't fit.

[WaterH2O]

Guys and Gals,

Just to digress a little from the actual topic. Does a fan used in bringing down the water temp also help to oxygenate the water at night since it is also sort of like agitating the water surface with all the air blowing at the top?

[Burnz]

From the impression i read from other threads, yes it does help oxygenated the water.

[soulfinder78]

I'm using 2 fan ( 1 Mr tornado and the other is those common fan sold at LFS) on my 4 feet tank. With room temperature at 30 deg i never manage to get it below 27.

Will be interested to know how's the fan arrange are, speed of fan and size of fan for those bros here who manage to get the temperature down to 25 using fan.

Thanks

[rebbot]

I wonder if anyone tried attaching a TEM setup directly to the outer layer of a tank. I thought it should work if the tank is small in size i.e. below 10 liters.

Will try if I manage to get one off ebay.

[kuruppa]

may i know what's a TEM setup?

[aquanatix]

Correct me if i'm wrong, a TEM chiller is a cooling device that uses fan technology to cool water,similar to the common aquarium fan but just encased in a "unit". Similarly,water is cooled when it passes by hence the drop in temperature. Unfortunately the TEM device brings down to a max of 2-3deg maximum and it works efficiently up to a maximum of 1.5FT tanks? There was another thread going on about the TEM chiller,so do feel free to read up abit.
Similarly like bro soulfinder78 i too would really like to find out how bros here manage low temperatures on bigger tanks?25deg on a larger tank with the use of fans sounds almost impossible?