Keeping our tanks cool in the summer?

[Pugwinkle]

I would love to hear from everyone that doesn't have A/C as to how I can keep my tanks cool throughout the summer. We are having a very hot and humid day today and my tanks have shot up in temperature.

Should I be turning off my heaters for the summer? Even with the heaters off the room temperature water is at 82 degrees.

Any suggestions would be appreciated.

[Anomaly]

There are two ways I know of to keep a tank cool. One is leaving the cover off (unless you have jumpers of course), and letting a fan blow across the water's surface. Or you could try floating a bag of ice.

[grimlock3000]

There is no need to turn off the heaters because they will never run anyway unless the water gets cold.

[CiRXSi]

Are there possible temp shock issues for the fish? One would think that the fish would just stay away from the bag if it was too cold. But some fish aren't always that smart.

[TankGirl]

The best way that I know of is to run a fan, as mentioned. The bag of ice method works, but it cools very unevenly and I prefer to hold off on using that except in emergency cases, like when a heater goes haywire and the water temp shoots up. Do you run lights on the tank? If so, they might contribute to the heat if they are incandescent or PC fluorescent, or even regular fluorescents can heat up a little.

FWIW, in my early years in the hobby I lived in South Florida and kept goldfish and oscars (not together ) in a house with no AC for 7 years. I never even owned a heater, and also kept the same individual fish the entire time without problems.

[grimlock3000]

If the room temp is 82F, how would blowing air across the top of the water lower the temp to less than 82F? Basically, how could the tank possibly get colder than the room temp by having warm air blown across the surface? Does the evaporation process itself create that much heat loss?

[shawmutt]

If you do have jumpers, you can do what the saltys do--replace the hood with a piece of eggcrate and have a fan blowing over the water. Just make sure the eggcrate is facing the right way for all the light to get in the tank (the narrower side should point down).

[Pugwinkle]

[quote="TankGirl"]The best way that I know of is to run a fan, as mentioned. The bag of ice method works, but it cools very unevenly and I prefer to hold off on using that except in emergency cases, like when a heater goes haywire and the water temp shoots up. Do you run lights on the tank? If so, they might contribute to the heat if they are incandescent or PC fluorescent, or even regular fluorescents can heat up a little.

Would it be okay if I left the lights off when it's this warm. Even if it's for a few days?? I don't have any live plants to worry about.

Do you blow the fan above facing down onto the water or can you just blow the fan at the tank?

[Pugwinkle]

Originally Posted by shawmutt

If you do have jumpers, you can do what the saltys do--replace the hood with a piece of eggcrate and have a fan blowing over the water. Just make sure the eggcrate is facing the right way for all the light to get in the tank (the narrower side should point down).

Do head and taillight tetras jump? What about Bristlenose Plecos?

[TankGirl]

I would not worry too much about the head/tail light tetras, and I would not worry about the bristlenose, but I do seem to recall someone having one (maybe a rubberlip) getting out and was found on the floor. Your call, or go with a piece of screen or the eggcrate (that stuff is cheap, and easy to snip to the proper size).

Blow the fan across the surface of the water if possible. This increases evaporation, which does indeed cool the water down (think swamp cooler in the Southwest).

[patryuji]

Originally Posted by grimlock3000

If the room temp is 82F, how would blowing air across the top of the water lower the temp to less than 82F? Basically, how could the tank possibly get colder than the room temp by having warm air blown across the surface? Does the evaporation process itself create that much heat loss?

Yes. The heat of vaporization for water is quite high. This is how an evaporative cooler works so well to keep you cool (when the humidity isn't very high).

If you have an empty "media" basket in your filter why not put a small bag of ice in that? Then right before nighttime toss the media basket (with bag of water) into the freezer over night in preparation for the next day.

Why not also turning the heater down 1 or 2 degrees to let the nighttime temps of the water to get slightly lower.

[hashbaz]

Like TankGirl said, evaporation can be very effective at cooling, but the effectiveness goes down as humidity goes up. At 100% humidity there will be little if any evaporation.

I think those fish should be able to tolerate 82 degrees. I don't know how hot it gets in ontario canada though.

[QTOFFER]

I didn't have aquariums until November of last year, so I have no idea how much of a problem, if any, overheating will be this summer.
I have AC units in the bedroom and livingroom, but I don't run them when I am at work- usually during the hottest part of the day. Even when I do run them, they do nothing to cool down the bathroom, where I have a 7 gal tank.

I found this link for a low-tech (cheap!) homemade chiller that may be of interest.
http://www.reefs.org/library/diy/diy11.html
EDIT: Sorry - you will have to cut & paste the link into your browser.

Where I work, we get several cold shipments every day - in big 10 gallon styrofoam chests full of frozen gel packs. I may give this a whirl if my tanks overheat this summer.