Chilling aquarium water during summer

[Sean W.]

Hi Everyone!

I just moved to a new apartment and I'm thinking about setting up a new tank, unfortunately my place is older and does not have central air, which is fine as I probably wouldn't run it even if it did have to to cut down on electricity usage. However, since it is an older place it doesn't have very good insulation, as we approach summer here in Los Angeles, I am fully expecting the inside of my house to reach upper 90's (mid 35C).

I can either get a window AC unit and cool the whole room all day/night to keep water around 82 max, which would use an immense amount of electricity, or I can chill the water directly.

There are obviously commercially made aquarium chillers, but I think I have found a DIY solution using peltier cooler or TEC1 units to make my own chiller. It could be more cost effective and its a fun DIY project.

I only have room for a 29 gallon tank right now, I'm thinking a Spotted Congo Puffer tank, so I don't need to chill a huge amount of water.

TLDR My Question is:

My concern is condensation on the outside of the glass, at what temperature will condensation form. If its 95 in my house and 82 in the tank, will my viewing experience be completely ruined by condensation?

I have never chilled aquarium water before so I have very little knowledge of this.

Thank you for any help!

 

[Rocksor]

Pick a group of fish that will exist in the aquarium without a chiller. There's quite a few out there readily available. It would also be important to not fully stock the tank. Also, just because it is 95F in the room, doesn't mean that the tank itself will 95F. The cool down in the evenings can prevent the tank from getting too close to room temperature. I keep a 55g glass tank in the garage that has an air temperature of 104F, but the temperature in the tank doesn't get more than 87F.

Condensation will only form during times of lower humidity, and won't affect what you see underwater.

 

[Jexnell]

Last summer I had went thru 30+ days of 90° plus days in an apt with no AC. I had two 125s and a 55.
First take the heaters out altogether wont need them till winter at this point.
My tanks fluctuated from 87° down to 79° at night and its normal for them to go thru this in the wild and will be perfectly fine. I had an Oscar, HRPs, tetras etc all lived thru it perfectly fine.
The one thing I did do is buy a case of water. Let some out of each bottle then freeze them. Then during the hot time of the day I set them in the hob filters. Run it under water a little as the ice can make load pops/cracking noises as it melts and scare the fish. So get most of this done before you set it in the hob/tank.

 

[krichardson]

Another reason all of my tanks are situated in the basement.I live in an older home and in the summer it rarely reaches eighty degrees down there on the hottest days.
I know it doesn't help the op at all but I just thought I'd share my thoughts on the subject.

 

[Sean W.]

I found a condensation (dew point of water) calculator online. It looks like water temperature, ambient temperature and relative humidity are all the factors at play when calculating when condensation will occur.

According to this calculator, with a relative humidity of 50%, and a room temp of 95F, condensation wont occur on the glass until the water temp reaches 74F, which is much colder than I would ever run it during the summer. I think RH 50% is a bit higher than what it will actually be, closer to 40% is probably more accurate, which brings the dew point ( the temperature at which condensation will occur on the outside of the awuarium glass ) down to 67F.

 

[pops]

I would not worry about it. set your heater to 75 or 78, and be done with it. the heat in the house not going to hurt your fish unless you running a cold water salt which would already have a chiller on it.

 

[TwoHedWlf]

First take the heaters out altogether wont need them till winter at this point.

Don't bother. They have thermostats and that's literally their entire reason for existing.

I can either get a window AC unit and cool the whole room all day/night to keep water around 82 max, which would use an immense amount of electricity, or I can chill the water directly.

That would be my choice, has the advantage of making the room far more comfortable for you too. I think here there's some regulation that over 25°C isn't considered suitable for occupancy.

Peltier coolers and DIY fridge based ones aren't particularly powerful or efficient. An aquarium chiller would definitely do the job, but it would make the room even warmer.

Keeping the windows open and blowing cooler outside air in will help. Obviously, less so when it's hot outside too.

 

[pops]

Rule of thumb for keeping a cooler house in hot weather, open the house up in the morning while its cooler, and closing it up when it gets hotter later in the morning. and run some fans, I am from cali, born and raised, the house will still get warm come 3 or so, but not as warm as if you left it open all day.

 

[Cardeater]

I'm not sure if it can lower the temp enough in your case, but I will say that having fans for evaporative cooling definitely works. I bought a small fan that blows onto my water through some plastic mesh. I got this idea from the old Real Fish Talk video I'm posting below. (Cory since changed the bane to Aquarium Coop Clips).

I decided to try this as my filters and powerheads warm up the tank even with the heaters turned off and I wanted to see if I could keep the water a little cooler.

Last year, I was wasting energy. My 125g would get water than I liked bc there's less airflow where it as and bc of the powerheads and the filters. I turned the AC colder which helped. The two 10g I have are directly under a vent so my heaters were keeping their temps up.

This year, I can keep those 10g cooler.bc the stock doesn't mind mid 70's or even low 70's. This time last year I was QTing clown Loaches so I wanted higher temps. I can keep the AC higher and just cool the 125g with my little fan.

Cory and Joel discuss various methods of cooling in this video which is where I got the idea of having a fan for my tank :

 

[phreeflow]

I have similar experiences as Rocksor and Jexnell, it takes a lot to raise water temps...I too had ponds outside in blistering direct sunlight in California for several summers and never experienced temps going up too much past mid 80s on the hottest days. I wouldn’t worry about it but if it bothers you, put a circulation pump near the top of the tank and make sure you have lots of surface movement and keep the lids off or run a clip on fan across the surface of the water. If you think it’s still too hot, add some ice. But again, unless you’re running a Reef tank or caridina Shrimp, most fish could handle the temps fine