Using car radiator as cooler

[KipperSarnie]

I just love it when I'm right!
but
I'm wrong again!🙁

 

[limz_777]

Looking at this from a different point of view.
When I was a child we had terracotta milk coolers.
The milk was placed in a saucer / pot of water with a terracotta dome over the top, The water from the saucer would soak into the terracotta & evaporate thus cooling the interior where the milk was....... Now could this not be possible run a pipe in the interior of the terracotta dome with aquarium water passing through it instead of the milk bottle?
Perhaps get a dome made or find a porous pipe to do the job.

Oh well! .... just a thought!🙂 But no running costs if you already have a filter running.

i got to know of this primitive method of cooling some time back , which some call it zeer pot cooler , so far i didnt see anyone run some test on it on a aquarium set-up ,might be interesting thou.

 

[Progen]

Many people have made quite effective tank coolers by mounting a load of PC fans into the hood of their tanks. If you run large diameter 12V fans on +5V, they run almost silently and can easily lower the water the water temperature a couple of degrees.

One particular summer, here in UK, when it was once hot, I lowered my tank temp from 32'C odd to about 26'C by just attaching a clip on fan (about 15cm diameter) to tank edge.

Now that's something worth trying although what was the dimension of that tank? Mine's a 48"er.

 

[ian_m]

Now that's something worth trying although what was the dimension of that tank? Mine's a 48"er.

Yes it was PC fans on a large tank, possibly 4-5 foot.

Only other thing is evaporative cooling, ie air flow across the surface only works in dryer climates, absolutely no good in the tropics as the air is already saturated with moisture, thus will not be able to take any more. The only solution in this case is proper refrigeration or for smaller tanks Peltier type devices.

 

[xim]

Yes it was PC fans on a large tank, possibly 4-5 foot.

Only other thing is evaporative cooling, ie air flow across the surface only works in dryer climates, absolutely no good in the tropics as the air is already saturated with moisture, thus will not be able to take any more. The only solution in this case is proper refrigeration or for smaller tanks Peltier type devices.

It still does some good. The air there are not really THAT saturated with moisture. (How can I know? 🙄).
In the rainy season, the evaporation rate will be lower but the temperature in this season will be cooler as well.
Actually, it is in the rainy season (there is no winter), especially around Nov-Dec when the temperature is at the lowest, that a non-chiller planted tank in this region looks at its best.
Final photos will be taken well before the summer comes in late Feb.

Fans absolutely help. I believe the OP could find some fellows in the same region for this kind of info.
http://www.my-mac.net/forum/viewtopic.php?t=1704

 

[limz_777]

It still does some good. The air there are not really THAT saturated with moisture. (How can I know? 🙄).
In the rainy season, the evaporation rate will be lower but the temperature in this season will be cooler as well.
Actually, it is in the rainy season (there is no winter), especially around Nov-Dec when the temperature is at the lowest, that a non-chiller planted tank in this region looks at its best.
Final photos will be taken well before the summer comes in late Feb.

Fans absolutely help. I believe the OP could find some fellows in the same region for this kind of info.
http://www.my-mac.net/forum/viewtopic.php?t=1704

off topic , but what happen to mac ? used to be one of mine goto forum .

 

[Bolota]

latent heat is the amount of heat the atmosphere will gain from the evaporated water vapor mass. The only change in the water side is a reduction of mass and of the total heat of that system (the tank) but it will not lower the temp of the water in the tank.....
To put it in simple terms: if you evaporate more, you transfer more water (in vapor form) to the atmosphere and that water will contains heat that passes from the tank to the room atmosphere. But the temperature of the water that remains in the tank is the same.

 

[ian_m]

But the temperature of the water that remains in the tank is the same.

Incorrect. The energy needed to supply the latent heat of vaporisation to evaporate the water, is supplied from the tank water. Thus energy is removed from the tank, lowering its temperature.

This is why we sweat, the evaporating water on our skin removes energy from the body, lowering out temperature.

 

[xim]

off topic , but what happen to mac ? used to be one of mine goto forum .

No idea. May be from competition from other platforms such as Facebook like many message boards 🙁. BTW, aquaticquotient.com is still active. Some MAC's members post there too. But today the system is down and seems to lose recent data from Dec last year up to the present. Yesterday it was still fine.

 

[Bolota]

The energy needed to supply the latent heat of vaporisation to evaporate the water, is supplied from the tank water. Thus energy is removed from the tank, lowering its temperature.

Yes, that is right. I'm sorry. There is an amount of heat you will pay to provide the kinetic energy for the particles to escape the water surface. However, you also loose heat with the water mass itself into the room atmosphere, so the total is maintained (that's what I should have said in the begining). Anyway, my point is that evaporation is only efective if you evaporate a lot. But that only happens if the room temperature is too high and/or too dry. But in that case you have temperature flux back into the water by contact and radiation.... So I cannot believe the fan method to be very efective in a closed room.

 

[roadmaster]

I once saw such a DIY chiller made from old portable fridge.
Extensive coiling(see meter's) of tubing ( plastic) inside the fridge, gave longer dwell time for cooling of water passing through the coiled tubing.

 

[ian_m]

I once saw such a DIY aquarium chiller made from old portable fridge.
Extensive coiling(see meter's) of tubing ( plastic) inside the fridge, gave longer dwell time for cooling of water passing through the coiled tubing.

I saw it too, but it was hopeless and didn't really work. Issues were:

- Fridges aren't designed to run the compressor 24/7, thus would not have a very long life.
- Fridges/freezers are designed to produce a temperature drop of 20'C (or 40'C for freezer) and aren't very efficient lowering the temperature the 10'C needed for an aquarium.
- Not very energy efficient running 24/7.
- Not very efficient transferring the "cold" of the fridge to the circulating tube (as it is plastic, not metal).
- Freezing up of internal cooler pipes occurred as not really transferring the "cool" out of the fridge very well.
- Well massively large for the limited poor cooling it provided.

So a proper chiller is the order of the day.

Someone hooked drinks cooler to his tank somewhere, but apart from being very large, very noisy and consumed 1KW power (a chiller is in order of 100-200W) did cool his tank.

As for someone above who said fans don't work, you need to tell the people selling fan kits
http://charterhouse-aquatics.com/sh...ms/jbl-8/jbl-cooler-300-aquarium-cooling-fans

These appear to match what I got in the summer 4'C drop using a clip on desk fan.

 

[KipperSarnie]

Now i'm not an educated man, far from it, but Progen the original poster states he is in the tropics so the way I see it is if the air temperature is 35c & your tank is at 33c then blowing the hotter air at the water will raise the water temperature not cool it!
I know when I worked in Singapore we used to put water bowls in front of the hurricane fans to cool the air & as far as I know the only way the water was cooled was when we topped it up.

 

[ian_m]

Now i'm not an educated man, far from it, but Progen the original poster states he is in the tropics so the way I see it is if the air temperature is 35c & your tank is at 33c then blowing the hotter air at the water will raise the water temperature not cool it!
I know when I worked in Singapore we used to put water bowls in front of the hurricane fans to cool the air & as far as I know the only way the water was cooled was when we topped it up.

Incorrect.

Blowing air over the water causes evaporation, evaporation requires energy and this energy comes from the tank water. Removing energy from the tank lowers its temperature. This is why we humans sweat to keep out body temperature at 37'C despite air temperature being once for me 46'C in Greece.

Evaporation requires energy, about 2200kJ/Kg for water. Thus evaporating 1Kg of water will require 2200kJ, which it will get mostly from the liquid water. The heat capacity of water is about 4200kJ/Kg/K. Thus roughly, evaporating 1Kg of water will lower 1Kg of water 0.5K ('C). This is how water powered air conditioners and fridges all work. They evaporate water or refrigerant, the evaporation taking energy from the surroundings, thus lowering its temperature and keeping you or your beer cool.

When camping years ago, before small fridges & site electrics became common, we used to keep fresh milk cool by placing it in a bucket of water and covering with a damp cloth (or even better an earthenware plant pot). The water evaporating kept the milk cool, just need to top up the water regularly.

In the tropics, provided the air is not saturated ie above say 70% (which of course it maybe) then blowing 35'C air over 33'C tank water, will induce evaporation thus lowering the tank temperature, no issue. You should easily be able to obtain 4-5'C drop with quite small air flows. Obviously you can get lower temperature with greater air flow but with greater loss of tank water.

 

[rebel]

Fans can achieve about 4c drop unless your tank is insulated very well. I kept water at 20C in a 5L styrofoam container with fan and continuous water top ups. Tap water was 18c and I needed to top off about 1L daily. Ambient was between 27-40.

 

[Mortis]

Unfortunately there are no cheap or easy ways to cool a tank. Im speaking from experience. Fans can cool your tank enough IF your ambient humidity is low due to evaporative cooling. The number of fans will obviously depend on the size of the tank, 4-6 120mm or 80mm should be sufficient on a four footer. If the ambient humidity is high then it might only lower the temps by a degree or two. Cross ventilation in the room will also help when using fans.
If your humidity is high like it is here in the tropics during summer then a chiller or AC is your only option I'm afraid. My tanks are in the bedroom so they get cooled to 22 by the AC which is switched on only at night and at the end of the day the max it rises to is 26 degrees.
Peltiers are only good for nanos. They need to be cooled themselves and consume a LOT more electricity on a bigger tank than an AC or chiller would.
So Progen, if your humidity is low, below 70 then you should be getting satisfactory cooling using fans, atleast 28 or lower.

 

[limz_777]

Unfortunately there are no cheap or easy ways to cool a tank. Im speaking from experience. Fans can cool your tank enough IF your ambient humidity is low due to evaporative cooling. The number of fans will obviously depend on the size of the tank, 4-6 120mm or 80mm should be sufficient on a four footer. If the ambient humidity is high then it might only lower the temps by a degree or two. Cross ventilation in the room will also help when using fans.
If your humidity is high like it is here in the tropics during summer then a chiller or AC is your only option I'm afraid. My tanks are in the bedroom so they get cooled to 22 by the AC which is switched on only at night and at the end of the day the max it rises to is 26 degrees.
Peltiers are only good for nanos. They need to be cooled themselves and consume a LOT more electricity on a bigger tank than an AC or chiller would.
So Progen, if your humidity is low, below 70 then you should be getting satisfactory cooling using fans, atleast 28 or lower.

quite true fan cooling only drop 1-2 c , always wonder how most claim it drop 4-10 c , there's another theory that number of fans doesnt matter as long as water evaporate from the tank

 

[rebel]

If you can insulate the tank and keep topping up, fans can easily do 4 degrees. My humidity is 50% though.

 

[Mortis]

They do drop the temps and keep them down even in the Tropics by 4-5 degrees but only during winter when the humidity is below 50 and ambient is 20-25 anyways 😛

 

[Progen]

This is how I've been cooling the tank for the past few weeks. It takes the temperature 1 or 2°C down so that's good enough. Can see plants and fishes improving. The higher / ambient temperature is incorrect because that's from the sensor behind the unit. Room ambient temperature should be higher. Room fan is on all the time except for on (tropic) cold days where ambient is around 26 - 27°C.