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How to Prepare a Tropical Aquarium for Winter Blackouts

Kylyssa Shay has successfully kept aquatic creatures for decades. Her fish-care advice has been published in "Aquarium Fish Magazine."

How to Prepare a Tropical Aquarium for Winter Blackouts

How to Prepare a Tropical Aquarium for Winter Blackouts

How to Keep a Fish Tank Warm in a Power Outage

When the power goes out in winter, you can grab a blanket and put a sweater on the dog, but your tropical fish or reef aquarium may be at risk of damage. A few simple precautions and a well-stocked emergency kit could save your freshwater or saltwater fish, live coral, aquatic plants, or invertebrates from illness or death due to cold-water temperatures or lack of aeration during a blackout.

So, don't worry about your pet fish or prized corals dying during the next Snowzilla or Snowpocalypse, stock up on the appropriate supplies instead! Read on to learn what to do to protect your tropical aquarium or saltwater tank during cold-weather power outages.

General Cold-Weather Tips for Tropical Fish

  • Move fish tanks away from windows to keep drafts to a minimum.
  • If possible, keep your aquarium in the room you'd be most likely to close off and retreat to in the event of a cold-weather power outage.
  • In case of a winter blackout, cover any windows in the room with blankets, sheets, or plastic and put a draft dodger or rolled-up towel under the door.
  • Hang out in the room where you keep the tropical fish tank to passively keep the room warm (thanks to your body heat).
  • Reduce the amount you feed your fish until the electricity comes back on to minimize the build-up of waste and degradation of water quality in your aquarium.
Necessary Supplies to Keep Your Fish Tank Warm During Power Outages

Necessary Supplies to Keep Your Fish Tank Warm During Power Outages

Necessary Supplies to Keep Your Fish Tank Warm During Power Outages

The essentials for keeping your fish tank warm during a winter power outage include:

  1. Mylar emergency blankets
  2. Heat packs
  3. A battery-powered aerator
  4. Duct tape
  5. UPS or uninterrupted power supply
  6. (A printed copy of this page)

Your kit should contain at least one Mylar emergency blanket, a battery-powered aeration device or air pump, duct tape, and as many 72- or 60-hour heat packs as you can reasonably store under the fish tank.

An uninterrupted power supply or UPS can provide hours of power in a cold-weather blackout, but it's best to have the rest of this kit on-hand in case the power stays out longer.

How to Use a Tropical Aquarium Blackout Emergency Kit

Once you have all of your supplies ready, here's how to make use of the emergency kit:

  1. Turn on the air pump: To protect your aquatic pets from cold-weather blackouts, start by connecting and turning on the battery-powered air pump as soon as the power goes out. For maximum oxygenation, the battery-powered air-pump power pack should be outside the Mylar emergency blanket when you are finished.
  2. Arrange the heat packs: Put four to six activated 60- or 72-hour heat packs evenly spaced around the aquarium. Attach the heat packs with a sticky-side-out loop of duct tape at the bottom edge of the outside of the tank.
  3. Wrap the tank in an e-blanket: Wrap the Mylar emergency blanket around the fish tank with the shiny side in; leave a bit of looseness around the heat packs. Tape the blanket together like a tent at the top. Use the duct tape to tape the blanket to the stand. Make sure that the power pack and the air pump are both outside the Mylar emergency blanket.

1. Mylar Blankets

Mylar will help keep heat in your tropical aquarium during power outages, and you will need one or more. They can usually be found in sporting goods stores and in the sporting goods departments of most major stores.

Decide how many you need in order to keep the heat in your tropical aquarium or reef aquarium during a blackout by measuring all the way around it. You should have at least eight inches or more in combined length of Mylar emergency blankets than the circumference of your aquarium.

When in doubt, get one more than you think you'll need. They are handy to have around and a double layer may provide more heat containment. A single 54" x 80" blanket will work fine for a 10-gallon tank. Two 54" x 80" Mylar emergency blankets will comfortably cover a 75- or 90-gallon aquarium.

2. Disposable Heat Packs

It's a good idea to have a good supply of emergency heat packs. 72-hour warmers are ideal but the 60-hour UniHeat warmers seem to be more readily available. A good rule of thumb is to use two heat packs per 25 gallons of aquarium at a time. So, if you have a 75-gallon aquarium, you may want to have 6 warming packs available for each 60 hours you may be out of power due to a cold-weather power outage. If you use another type of warmer, be sure to follow its specific instructions.

  • Important: Please remember that the heat packs must be used outside the tank—never put them in it!

3. Battery-Powered Aeration (Bubblers)

Tropical fish and reef tanks will benefit from steady aeration during stressful times such as cold-weather power outages. While bubblers aren't used much in saltwater set-ups, they provide water movement quite well in an emergency. A cheap, battery-operated bait aerator will do in a pinch, however, you'll need to stock up on batteries before a blackout happens. While your usage may vary, these devices usually work for about 8 to 16 hours on a set of batteries.

I have a couple of battery-powered air pumps for use during power outages, both of which will operate vigorously for about 12 hours per charged D-battery. You can store a spare battery right inside the casing.

  • Important: Just so you aren't surprised, please be aware that battery-powered aerators are usually pretty loud in operation.

4. Duct Tape

2" Duct tape will be used to stick everything in this kit together to keep your aquarium warm. While any Duct tape will work, I prefer Duct tape that's at least two inches wide. It is easier to tape along the side of a Mylar blanket with wider tape and it gives you more sticky surface area to grab whatever you need it to.

5. UPS or Uninterrupted Power Supply

A UPS or uninterrupted power supply can protect your tropical aquarium from winter power outages for several hours. While most uninterrupted power supplies don't provide more than a few hours of power, they can protect your tank automatically and probably long enough for you to get home if the power goes out while you are out for less than eight hours. You can then take other steps to keep your fish safe once you get home.

The length of time your uninterrupted power supply will provide power for during a blackout depends entirely on what you have plugged into it. I suggest trying a dry run by unplugging the power supply and testing it to see how long it lasts so you'll have no surprises if it is needed later.

I like the power supply shown below because four of its outlets automatically switch to the backup power supply if the electricity goes out. That way, one can pick and choose what to have backed up with an emergency power supply. For winter use, be sure to plug the heater into the automatic backup outlets on the strip.

Porky, the porcupine puffer fish smiles for the camera.

Porky, the porcupine puffer fish smiles for the camera.

Always Be Prepared

While a backup power supply can provide hours of power, it's still a good idea to have the rest of the cold-weather emergency kit available in case the blackout lasts longer than a few hours. Also, if the power stays off long enough to cool down your home, simply providing power to your aquarium heater may not be enough to keep it warm so, at the very least, a Mylar emergency blanket should be wrapped around the tank to keep the heat in.

© 2011 Kylyssa Shay

Is Your Tropical Aquarium Ready for Cold-Weather Power Outages?

RinchenChodron on June 24, 2014:

Great advice and pretty easy!

rajatwilightdream on January 20, 2014:

Excellent tips! I do have a Tropical Aquarium in a small way. For uninterrupted power supply, I have connected my Inverter to the Aquarium power point. My fishes are always enjoying. Keep writing!

anonymous on March 12, 2013:

When we kept tropical fish I always worried what would happen if we lost power for days. This is an excellent resource.

anonymous on March 06, 2013:

Thanks for the great information.

moneyrat on March 04, 2013:

I have a computer UPS connected to my Discus Fish aquarium. It can keep hold power for several hours. This is specially for nighttime.

anonymous on February 28, 2013:

I never thought about what to do in the event of a power outage! I take care of a 300 gal tank at my church! Thanks for this info!

makorip lm on February 27, 2013:

It cost my homeowners insurance over $4000 when our 8 day power outage here in Seattle blew out my 6 year old reef aquarium. Outages are real and costly. Good lens!

Nnadi bonaventure Chima from Johanesburg on February 26, 2013:

Highly informative lens ,thanks for sharing

Fabian Cornejo from Colorado on February 26, 2013:

I don't have a tank but this makes me think of Hawaii and how it must be like your own little piece of the tropics.

anonymous on February 24, 2013:

Thank you for these wonderful tips :) Congrats for your LOTD!

agagata lm on February 23, 2013:

I wish I had read it two weeks ago when the electricity went and I lost 5 fish because of it... I'll bear it in mind for the future though. Thanks!

TCG master on February 23, 2013:

OMG I love my fish this lens is SO helpful!!

street2linen on February 23, 2013:

Great lense and information about preparing ones aquarium.

Vikki from US on February 23, 2013:

Wow. I'd never even thought about that issue before but it certainly is one. (I guess that kinda reveals I don't have an aquarium or fish ;)--- Awesome tips--very helpful! Congrats on lotd too.

Tom on February 23, 2013:

Great tips. I love tropical fish. Congrats on LotD!

anntag on February 23, 2013:

That's really good to know how to take care of your aquaruim fish in an emergency.

jntnevins lm on February 23, 2013:

Very nice lens. I don't have an aquarium now but I used to. When I had one I didn't think about having a kit. This is a great idea.

mrknowitall54321 on February 23, 2013:

Well done on achieving the lens of the day, very good lens with lots of fantastic information.

Elyn MacInnis from Shanghai, China on February 23, 2013:

What wonderful ideas. I love your photo of the sweet fish in the introduction. You wouldn't want to lose such a sweetheart just because the electricity went out! SquidAngel sand falling gently on you and your tank!

Camp April on February 22, 2013:

Congratulations on LOTD. Way to go. Lots of great tips I hadn't even thought of. Thanks

Tara Wojtaszek on February 22, 2013:

Lots of great tips to keep your aquarium safe. Congratulations on LOTD, blessed!

Judith Nazarewicz from Victoria, British Columbia, Canada on February 22, 2013:

Congrats on LOTD! Really great tips for preparing your aquarium.

Hannah Writes on February 22, 2013:

Congrats on being LotD! Blessed.

livingfrontiers on February 22, 2013:

This is such a great idea, and it makes me happy to know I am not the only one who worries about this exact problem! I am very grateful for your knowledge!

Wish List Gifts on February 22, 2013:

Thanks for this - I actually lost a small tank to a power outage right after I started the hobby. Lots of hard work and lovely animals lost.

cleanyoucar on February 22, 2013:

Great tips! Thanks for sharing them.

pigwear on February 22, 2013:

Great lens...I haven't thought about the need for this but in a northern climate it would be very usefule.

TopChristmasToysGifts on February 22, 2013:

Congratulations on Lens of the Day.... Thanks for the tips in case of power outage.

Sara Krentz from USA on February 22, 2013:

I've been wanting an aquarium, but it wouldn't have occurred to me to have an emergency kit for a power outage. Thanks for the info.

heehaw lm on February 22, 2013:

although i do not have any salt water fishes, but this is a good knowledge for me. thanks for sharing.

nicey on February 22, 2013:

I don't have a tropical acquarium.Congrats.

TommysTips on February 22, 2013:

Congrats on LOTD - great information on keeping your fish safe and warm!

Malu Couttolenc on February 22, 2013:

I don't have a tropical fish aquarium now, we used to have one some years ago and I know what is not to be prepared for power outages. We would like to have one again and thanks to your tips we will be prepared this time. Congrats for your LOTD! :)

tommydillard on February 22, 2013:

thank you very much about these ideas i never even thought of it cause i live in sunny California

nhotdeals on February 22, 2013:

Great ideas, granted I do not have fish right now but I never thought about it

Resident-Nerd on February 22, 2013:

Very nice information. Many people forget about there pets in these conditions. Thank you. Congrats on LofD.

JadaFuego on February 22, 2013:

Great LOTD!! I am sure my fish would thank you!!

wyzeguru on February 22, 2013:

I'd never even given this a thought! Our power supply hardly ever goes off but that's no excuse not to be prepared is it?

anonymous on February 22, 2013:

Good stuff, sound information. Congratulations on getting LotD!

Perrin from South Carolina on February 22, 2013:

Really useful info. Congrats on LOTD!!!

rdcbizz on February 22, 2013:

I love aquariums.

MartieG aka 'survivoryea' from Jersey Shore on February 22, 2013:

Good information! Congratulations on a well deserved LotD! :>)

zafsot on February 22, 2013:

This is a great lens, i am new here and i find squidoo just amazing

anonymous on February 22, 2013:

I was here a while back and remember being so impressed that I had not seen this information anywhere else and would imagine many have faced this situation with widespread power outages. Congratulations on LotD honors!

writerkath on February 22, 2013:

Whenever the power goes out at home (NH), I'm usually grateful I have the woods (backup "outhouse"), gas stove, and woodstove for heat... But I have sometimes thought about certain things like this... "What if someone needs some medical necessity that uses electricity..." but I have to say I hadn't thought about aquariums, simply because I do not have one. But this is very important for people to do have one. I hope that people who have aquariums find your lens and prepare. Nice, thoughtful (and thought provoking) page here, Kylyssa! Squid Blessed! :) Kath

cyberflutist on February 22, 2013:

I've never had a tropical aquarium, but they are beautiful and it would be a shame if one were damaged in a power outage.

Fox Music on February 22, 2013:

Thank you for sharing this lens "How to Prepare a Tropical Aquarium for Winter Blackouts" and congrats on Lens of the Day !!

Sharon Berry from Michigan on February 22, 2013:

Since I have never had an aquarium I've never given any thought to people who do and what would happen in a blackout. What a great lens with so much good info for saving your fish. Thanks for sharing.

vectorland on February 22, 2013:

Great lens and congrats on getting LOTD also :)

Bonfire Designs on February 22, 2013:

Congratulations on LOTD - great emergency information!

LeeD LM on February 22, 2013:

Great information - I actually just setup a reef aquarium (its still cycling so no living creatures yet) and we just had a huge storm. I was afraid of losing power and I did get a battery powered aerator but never thought about a mylar blanket. Thanks!

Pastor Kay on February 22, 2013:

Car jumpstarters usually have a spot to use as a regular outlet. You could use one of these and then recharge with your car (if you've got one).

JoshK47 on February 22, 2013:

This is an incredibly useful lens - never even thought about this before! Congrats on LotD and here are some SquidAngel blessings for you!

poldepc lm on February 22, 2013:

Congrats on LOTD

Faye Rutledge from Concord VA on February 22, 2013:

Great information to have. Congratulations on LotD!

LadyDuck on February 22, 2013:

Great lens of the day. Very good tips to protect our little friends the tropical fishes

soaringsis on February 22, 2013:

Thanks for sharing info. Congratulations on your LotD.

restaurantsinlebanon on February 22, 2013:

great lens with nice ideas

anonymous on February 22, 2013:

That is Great. Great tips and ideas.

Elaine Chen on February 22, 2013:

congratulation for the LotD and Purple Star reward; I just send this Lens URL to my best friend who love tropical aquarium.

Robin S from USA on February 22, 2013:

Congratulations, this lens was selected as LotD today. You can read all about it here:

NewUsedCarsSacramento on February 22, 2013:

Congrats on being LOTD. Id love a tropical aquarium.

Carpenter76 on February 22, 2013:

Nice lens. I like an aquarium, but I think it's so much work!

Tarra99 on February 22, 2013:

Congrats on LOTD Kylyssa

anonymous on February 22, 2013:

Congraulations on LOTD

JeffSawyer on February 22, 2013:

Congrats on being LOTD

lav777 lm on February 22, 2013:

great information:)

racingdatabase on February 22, 2013:

Great tips - we live in Scotland and regularly have outages here! :)

WriterJanis2 on February 22, 2013:

Good information to know.

Rose Jones on February 22, 2013:

Very helpful, well put together and useful. Blessed.

anonymous on February 22, 2013:

Aquarium care is so important and is often overlooked. Great lense!

Lori Green from Las Vegas on February 21, 2013:

My brother had this exact problem with his tank during Hurricane Sandy. He was out of power for 2 weeks and worked hard keeping his fish alive. This included boiling hot water on a BBQ for them. He lost a few but most survived. I told him to set his tank up at the home of a friend who had power, but he kept hoping the power would come on.

Fay Favored from USA on February 21, 2013:

Congratulations on LotD. Proper care for an aquarium is something people may not think about during a power outage. Nicely done.

Jogalog on February 21, 2013:

Congratulations on LOTD! I don't havea an aquarium but I'm sure I'd find all this information very useful if I did.

CampingmanNW on February 21, 2013:

Congratulations, I see why you won a purple star and LOTD. Excellent Ideas all. I have used similar tricks to keep my Koi ponds aerated and warm enough in the Pacific Northwest Winters. Nice job on this lens

SteveKaye on February 21, 2013:

Congratulations on receiving the LOTD. This is very good.

corydoras on February 19, 2013:

My tropical aquariums over the years have weathered multiple power outages without problems or anything more than a blanket wrapped round them and some styrofoam insulation, but I don't believe they've ever dealt with anything longer than 12 hours. Water has a high heat capacity, which means it cools much slower than air and a short power outage doesn't do too much harm to the average freshwater tank - unless it has been overstocked. Then aeration becomes a big deal and backup aeration is essential. I couldn't find a battery-operated pump when I had fish, which is why I didn't use one. I haven't kept marine, but wouldn't be surprised if they were more sensitive. You've many good ideas here. I think I'll try to find a mylar blanket for my lizard tank. I already have heat packs for her.

BillyPilgrim LM on October 31, 2012:

Good tips! I'm just starting to keep fish so this is very useful. Thanks x

sherioz on October 09, 2012:

I used to keep fish in a huge tank. We didn't have problems with cold, but if the electricity goes off then the filters shut down. This is an excellent article for anyone relying on electricity for their tank.

anonymous on August 08, 2011:

I don't have a tropical fish aquarium but I can sure understand the need to be prepared with an emergency kit for those winter power outages, we sure do get them in Fargo and the apartment cools down very quickly in cold weather. I have not seen information on this anywhere else, well done Kylyssa.....and the tropical fish of the world thank you!

huvalbd on January 22, 2011:

Clever solution--I like reading your lenses, which often teach me clever solutions.If you have a way to boil water, perhaps in a pan in the fireplace, rechargeable heat packs could be used too. To recharge, boil until the insides are entirely liquid again. To activate, through the covering, "click" the metal disk inside which starts the chemical reaction to release the heat. They should go through as many as 500 recharges before being worn out and needing to be discarded.

anonymous on January 21, 2011:

This is a beautiful lens on how to take care the temprature of aquariums for warm tropical fish.

Jack on January 21, 2011:

This is a great topic. Blessed by a Squid Angel.

anonymous on January 21, 2011: soon as I read your tips...nice lens