How do you cool a tank?

So it got to be 90 today and is currently 81 in the house. The next few days are supposed to be really warm and so our tanks will also be really warm. I have done the whole float a frozen water bottle thing before, but its frustrating to have had fish stress and die from temperature changes. And unfortunately keeping the whole house at a cooler temp isnt an option, so ideas for until we move please

leave things closed up and dark during the day/the heat of the day. also leave tanks without heaters or with them turned down so low they barely turn on. also daily water changes to help keep the temp down are decent ideas. open windows and doors at night to keep the house cooler the next day.

Cold water changes, daily. You shouldn't have to touch the heaters cause if the tanks are at 90, the heaters shouldn't be coming on.

Yeah keeping this place at a livable temp has been a pain. So ready to move on! We keep the lights on the tanks off most of the time too. The only thing with water changes is that sometimes the water that comes out through the sink is just as warm as it is outside! There are some major insulation issues with the house so I think our pipes heat up easily. I dont think we are quite to that point. so hopefully the really warm wait until we leave.

Nothing wrong with using the outside faucet

box fans..take of any lids of your tanks and set box/window fans blowing down on to them

its how swamp coolers work. ^_^ always seemed to work well for me.

When I do water changes I use 2 hoses, one from outside with straight cold water and one from inside with hot water.. I've found it makes my tank at the perfect temp everytime.. During the summer it helps a lot with keeping my tank temps down too..

I would not recommend using any hot water, regardless of the time of year.

i would not do hot and cold on glass either wouldnt it break

no it wont, but thats not why I said that I dont recommend it.

i simply suggested turning the heaters down to cover all the bases. as for not using hot water ive never encountered any issues doing it in all my years of fish keeping, heck i cant NOT do hot water for the discus.. temp swings are a no go. but i can understand your fear for foreign contaminants

I would do the cold water changes daily, and Kaosu's idea of a fan is a great idea also. Doing both of these should keep everything at a reasonable temp. GL.

Why would you ever do hot water changes unless you had money invested in a hot water tank purifier?

And cooling a tank in eastern wa... turn off your lights take off/open your lid. Do a COLD water change from the tap. You get water from the mountains water changes of 30% to 40% will be enough to keep temps at bay. Do them in the afternoon. Make sure your heaters are working properly.

i do a cool water change at about 12:30 everyday when it get seriously hot i have a smaller tank's compared to most so they get hot fast being in my tiny room (would be bigger but tanks lol)

I've worried about this too. Most of my tanks are upstairs in a room above the garage and it gets hotter than heck when it's hot outside.

With multiple tanks, I can't do enough water changes every day to keep the temp where I want it. I can't open the lids on most of the tanks because my fish are jumpers and I've lost a few that way.

What I do is make sure that I keep up with regular maintenance (50% water change each week) and keep the tank lights off and hope for the best. When the water is clean, the higher temperatures don't seem to bother my fish. I know that fish survive raised temperatures for several days when they are being treated for some diseases like ich.

Hey Madness i'm just curious why you wouldn't use hot water to do waterchanges ?? If i dumped 150 gallons of cold water in my tank all my rays would be doing back flips and dead ?? I've done the hot water hose and cold water hose for my water changes for years and haven't had any issues so far ??

I have addressed this several times on numerous threads. I will just say this, have the hot water from your tank tested straight water, then with prime or whatever you use. You will be amazed at what is found. Your rays may show no signs now, but give it time. Its like drinking soda all your life, nothing going on now, but it will . If you need to add warm water than put cold water in a holding tank heat it up then add.
All in all its your decision, all I can do is try to educate, and to help on this matter but it comes down to the hobbyist.

No problem, thanks for the info.. I just hadn't seen the subject with adding hot water brought up before.. didn't mean to beat a dead horse.. I'll have to test my hot water and see what i find out..

I didn't mean to come across as sour. I have tried to point out the facts on several occasions on many forums. Just to get people that are not willing to listen or even consider that there is a serious issue with it. I had one guy come on and say "hey, I just did a hot water change in my tank, and the fish all smiled" or something like that. Some people are shallow minded and are never open to change. They figure they don't need to learn something new cause they have beendoing it this way for ever. I am always learning, and when I come across something that I feel is a serious issue in the hobby, I feel that I need to address it. I strongly feel and am very passionate about the issues associated with using the hot water from your hot water tanks.

I think that I will take all my research and make some phone calls, and add more documentation, and write an article on it. Hmmmmmm, I just may do that.

madness wrote:

I think that I will take all my research and make some phone calls, and add more documentation, and write an article on it. Hmmmmmm, I just may do that.

I think that's a great idea. Or at least have it as a topic of its own if there isn't one already.

hbluehunter wrote:Hey Madness i'm just curious why you wouldn't use hot water to do waterchanges ?? If i dumped 150 gallons of cold water in my tank all my rays would be doing back flips and dead ?? I've done the hot water hose and cold water hose for my water changes for years and haven't had any issues so far ??

Ok so this I think is pretty self explanatory. If there is a warning for people what do you think this would do to fish over prolonged periods of exposure?

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Also: I can't remember where I got this snippet from but it wasn't written by me I just had the text saved to a txt file anyways enjoy.

You also get a lot of calcium carbonate build up at the bottom of your tanks. It can look like sand but it isn't. Here are some of the side effects of calcium carbonate on people:

may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome when using Calcium Carbonate:

Constipation; headache.

Seek medical attention right away if any of these SEVERE side effects occur when using Calcium Carbonate:
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); loss of appetite; nausea; severe or persistent constipation; vomiting.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.


Water Content Problems
Sulfates and sulfides are the most common offenders in water systems. Sulfates are a type of mineral that can enter your water system and cause scale build-up in your pipes and tank. This can happen in pipes throughout your home, but may be more common or more noticeable in your water heater, which will begin make noises as the scale builds. Some bacteria can live in pipes and oxidize the sulfate in a dark slime that can block pipes or stain clothes.

Sulfide gas is produced by a different type of bacteria that live primarily in your water heater and change the sulfate in a related compound. This sulfide is what gives water the classic "rotten egg" smell and taste. This gas can also be very corrosive to metal piping.


That is just one of many things you can take a look at. But in my opinion if there are this many warnings for us in regards to our hot water tanks then it is a safe bet to assume it isn't any better for our beloved pets.

One other thing I would like to add to this, thanks Seattle23, how many of you are aware of the warnings and dangers of using hot water from your tanks to cook with? You always use cold water and heat it. How many of you have heard that you shouldn't brush your teeth with warm water? Why do you think that dishwashers are designed to heat cold water? Just a few things to think about. Yes we all take hot showers, And yes there are studies out there about taking in these toxins through our skin.

Just a couple more things to think about. If you are curious just call your water company. They were the ones that pointed out my faults years ago. They even came out and tested the water for me, just to prove that the water from my hot water tank, is not safe. Regardless if you use Prime, or any other additive.

Thanks for all the good info.. Looks like i need to get off my butt and get my drip system going that i've been putting off for 3 years now..lol Then it'll be no more hot water for me either..

hbluehunter wrote:Thanks for all the good info.. Looks like i need to get off my butt and get my drip system going that i've been putting off for 3 years now..lol Then it'll be no more hot water for me either..

How big are your water changes? I mean I can do up to 50% cold water changes and only see a 4 degree drop in water temp. I usually only do 30% to 40% though. Other alternative is obtain a big holding tank and let it hold water to room temp. Just throw an airstone in there so it does not sit still. Pump into tank with water pump refill after water changes so it is ready for your next water change. Fairly cheap to find a big holding tank.

I do a 150 gallon water change on my 300 once a week.. aka 50-60%.. Even the way i was doing it with half hot water and half cold it still drops my tank temp 5-10 degrees after the hw heater is drained..

hbluehunter wrote:I do a 150 gallon water change on my 300 once a week.. aka 50-60%.. Even the way i was doing it with half hot water and half cold it still drops my tank temp 5-10 degrees after the hw heater is drained..

I agree, wow. I do 50% changes on a 20 gal, and it only drops from 82 to 74. Not doubting you, but that's crazy

my 135 dropped from 80-68 with a 70% cold water change yesterday which was a bit too much for my comfort level. i do too large of wc to use only cold water all the time but i try to keep the water cool out of the tap and never warm to the touch

I think some could missed the point. Even a "little bit" of warm water is using water from the hot water heater. The fish still are exposed to many heavy metals and contaminants.

I just installed a brand new tank so I know I have no build up on the bottom but I was shocked how much crud was in the old one. The original plumbing had a small bit of galvanized pipe mixed in with my copper. This of course causes a reaction and it causes the sacrificial anode rod to deteriorate and thus rust out your tank.

One thing that is necessary if you do decide to mix warm in is to make sure you flush out your water heater yearly. Or do smaller more frequent changes and just use cold.

Fishman, i'm telling you, like dmd said, don't even turn on the hot water. And D regardless if you flush your tank, it is a dark warm place full of moisture, things grow, and they are not good things.

like stated I change too much at a time to use only cold and haven't had any problems with water quality or health of my fish. got my water tested at my buddys pool shop and there weren't any problems with the water out of hot, cold and more importantly out of the tanks. so I'm goona keep doing what works. mel changes 80% on his 600s and I couldn't imagine him using only cold or it would streas the crap out of the fish. and with a temp change of 8 degrees a couple times a week it may stress out the fish and shorten lifespan

Betty wrote:

madness wrote:

I think that I will take all my research and make some phone calls, and add more documentation, and write an article on it. Hmmmmmm, I just may do that.

I think that's a great idea. Or at least have it as a topic of its own if there isn't one already.

Like you said, It's up to the hobbyist madness. We have both been in this hobby for a few years now and it's about learning different things and applying that knowledge and imparting that to others who have questions or have experienced similar things.

fishman09 wrote:like stated I change too much at a time to use only cold and haven't had any problems with water quality or health of my fish. got my water tested at my buddys pool shop and there weren't any problems with the water out of hot, cold and more importantly out of the tanks. so I'm goona keep doing what works. mel changes 80% on his 600s and I couldn't imagine him using only cold or it would streas the crap out of the fish. and with a temp change of 8 degrees a couple times a week it may stress out the fish and shorten lifespan

Fishman, I know Mel personally and he doesn't do 80% water changes on his 600 gal. tanks. Granted he does do approx 30-45% water changes on his 600 weekly and also does small water changes daily or every other day on them. The only time I have seen him do large water change was on his 1000G when he had a severe case of infection was that was introduced by another fish he had put in there...

I'm "fortunate" in that my community well has arsenic levels above the federally-mandated max (19ppb; max is 10ppb). Because of this I've used RO water for all drinking and cooking for almost 3 years now (let's nevermind exposure before that...). I don't use that for my fish though.

So today I went and did the "white cloth" test on the output of my water heater and YUCK, lots of crud coming out of there. I'm going to flush it shortly... and see what I can do to limit how much warm I use in my tank changes (I've been doing that already, but it looks like it's a good idea to cut it back as much as possible).

Thanks drd, yes Mel is very meticulous about his water. I picked his brain last year when I had an issue with my Dovii. He does exactly what drd stated. Never large water changes. in fact I don't understand why people do this. whether you are using cold, hot our warm I would think that a 75% water change would stress them out.period. I understand your fish are doing well and they look great. But eventually it will catch up.

Like I referenced earlier, you being a work out nut like myself can understand this, if you keep putting toxins in your body eventually it will catch up. You feel and look healthy now, but your health will diminish, you will start to get sick more often, flus and colds that you didn't catch before all of a sudden, your catching now.

Same goes with your fish, or any pet for that matter. Feed your dog or cat Safeway cheap food, and it will start to affect them. Take care of them and feed them good food, and they stay healthy and live long.

Just my 2 cents.

looks like im gonna change my wc schedule and use only cold water. i was definitely mistaken on what i read about mel's routine.

going from twice weekly 40-60% to

mon: 30%
tues: 10%
wed: 10%
thurs: none
fri: 30%
sat: 10%
sun: none= 90% weekly, all with cold only water. thanks guys

I always use cold water for my water changes... if temp is still too high between water changes, (I change water 1 a week at most) I make sure my filter is making a big splash... so if I have a HOB filter I just dont fill the tank to the top.... or if I am using canisters I make sure the output is above the water line.

hrmm. may have to get on board this gravy train. been doing warm changes for years with no ill effects (visible ones at least) and i dont like using carbon so perhaps its time to start up doing this. either way its not feasible for the discus tank but all the rest are just meh in my mind.

Anthraxx wrote:hrmm. may have to get on board this gravy train. been doing warm changes for years with no ill effects (visible ones at least) and i dont like using carbon so perhaps its time to start up doing this. either way its not feasible for the discus tank but all the rest are just meh in my mind.

Seattle23 raised and bred Discus for years doing it this way. Maybe he can chime in a give a little insight on his experience with Discus.

Anthraxx wrote:hrmm. may have to get on board this gravy train. been doing warm changes for years with no ill effects (visible ones at least) and i dont like using carbon so perhaps its time to start up doing this. either way its not feasible for the discus tank but all the rest are just meh in my mind.

You can have a water storage bin which you replenish after every water change. Or you can just add one more water change day and decrease the percentage you change out thus negating the need for warm water mix. My discus breeders were just fine and infact spawned even more so due to the temp change. But again if this is working for you and you have not seen any ill effects then do what works for you. But sooner or later the toxins will reach a breaking point imo.

Back to the topic of cooling a tank down, if you've got fish that are jumpers you can make a lid with hardware cloth so that you can take the hood off the tank. Usually air stones and pointing fans at the tanks works well enough for me.