Almost everyday somebody calls us with an aquarium emergency. Though occasionally we are surprised by an odd fish tank fiasco, we have heard (and helped) callers in myriad situations. A hurricane is about to make landfall. A tree has knocked out a power line. A child just peed in the aquarium. Your prized fish just broke out in spots. The tank has sprung a leak. The dog chewed the pump cord. And so on.

We are here to help, and happy to do so, but in the midst of an aquarium catastrophe there is only so much we can do to help when things have already gone south. This is why we highly recommend that you prepare in advance for something to go wrong. You have invested a lot of time, effort and money into your aquariums. So, why not be prepared?

You don’t have to build a bomb shelter for the apocalypse in order to be prepared for an aquarium disaster. With only a little preparation and a few items you can set yourself up to withstand most problems that will come your way. Here is our list of seven great ideas which will set you up for success when things go south.


Water has rightly been called the elixir of life. The single most vital aspect of an aquarium is water. So, wise aquarists keep water ready at all times, and the more the better. Freshwater systems should have de-chlorinated, oxygenated, and heated replacement water on hand. Saltwater aquariums should also have backup water ready to go in the midst of an emergency. Having extra salt mix on hand is also important. Once I did something epically klutzy during routine maintenance and broke the glass on a full reef aquarium. As water pored through the crack I had made, panic began to set in. The only thing that saved the inhabitants was a reservoir full of heated saltwater and a Rubbermaid bin ready to house everything. Ready water is the single most important thing you can do to be prepared.


Next to water, there are two basic things your aquarium needs to keep the inhabitants alive: oxygen and heat. Nature can be unpredictable. If you want to be prepared for an extended power outage (you do want to be prepared, right?) then you need a way to take care of both of these.

Once the pumps turn off and water stops circulating, oxygen levels will fall quickly. On the high end, some powerheads, like the EcoTech Marine VorTech and Tunze Stream, have optional battery backups. With a battery backup, should the power fail the backup immediately kicks in so the pump keeps running. These can keep water moving for days. On the more economic side, a battery powered air pump can mean the difference between life and death for your aquarium. A battery powered air pump will both oxygenate and circulate water. For larger aquariums, multiple battery powered air pumps are necessary. Be sure to have batteries on hand should the power stay off for long.

Heat is the other aspect you must be prepared for. During warmer months the temperature can quickly rise to dangerous levels during a power outage or chiller failure, sapping oxygen and endangering the fish. Opening up the windows for a breeze may help a bit, but often is not enough. I recommend keeping a few plastic soda bottles filled with water in the freezer. Drop one into the sump (or main tank) to help bring the temperature down. But, be sure to monitor the aquarium. Cycle the bottles out as the ice inside melts.

In colder months, the problem will be keeping the temperature up. The first thing you should do is to wrap the aquarium. Newspaper or blankets wrapped around the aquarium and secured with tape work great to insulate the aquarium and prevent heat loss. Then you can warm up water and put it in those bottles you had in the freezer. Be careful not to make the water so hot that the plastic melts. Then, as the bottles cool off you can heat more water and repeat the process.


There are a few items in your aquarium that are absolutely necessary to keep the inhabitants alive. You can go days without lights, a protein skimmer, or a calcium reactor. But, you should own a backup for each critical item. The backup parts don’t need to be the highest quality. They just need to be serviceable. A heater is necessary to keep the water warm. A powerhead is necessary to keep the water flowing.  For a system with a sump or refugium, a backup pump is a great idea. I also prefer to have backup impellers on hand, since impellers are more likely to break than the pumps. Look over your system, think of anything that would create a serious problem should it stop working, and have a backup. Usually these items won’t be sitting in storage because they can be used for your...


Often, the best way to prepare for an emergency is to prevent an emergency from arising. Nothing should enter your aquarium before being quarantined for weeks. During quarantine, observe your fish for disease and parasites. Check your coral for pests like aiptasia. Should one of your fish or coral need to be isolated, your quarantine tank can be put into use as a hospital tank. A basic quarantine system will include a simple filter (like a sponge filter), a heater, and a light (if you have coral). In addition, your quarantine tank can serve as part of your emergency water supply. Just know that a tank which has been treated with copper should never house invertebrates like coral, nor should the water be used in any tank with invertebrates.


Your house probably has a few basic medicines that you keep on hand. Your fish tank should be no different. Having a few basics in your kit can go a long way in treating diseases and parasites. Often, the difference between life and death is speedy treatment. Seachem Cupramine is great to have in your kit for the treatment of external parasites like Ich and Marine Velvet. You will also need a copper test kit in order to dose properly. API Pimafix is a good medication to have on hand for the treatment of various fungal and bacterial infections. A medicated food, like New Life Spectrum Thera-A, can also assist with internal parasites. Keep in mind that some medications have expiration dates. Follow all instructions carefully and research well before using any medication. At times, the medicine can be more dangerous than the disease, especially in inexperienced hands.


UV sterilizers are a preventative measure that can help you avoid problems in your tank, in particular with parasites. A UV sterilizer is a water filter that blasts the water with ultraviolet rays. Parasites, algae, and bacteria that pass through the filter will either be killed or sterilized so that they cannot reproduce. As a bonus, sterilizers make the water clearer. While a sterilizer will not kill any parasites on your fish, it will reduce the amount of parasites and bacteria in your aquarium water, reducing the chance for an outbreak in your aquarium. Sterilizers are a staple of professional aquariums.


There are a few basics that I keep in my aquarium emergency kit. Silicone glue can be used to patch up small leaks. Teflon tape will solve some plumbing leaks. There are certain plumbing parts that are worth having extras of. Hose clamps wear out. Check valves get stuck from time to time. Ball valves can stop working properly. Bulkhead seals can deteriorate. An aquarium part cleaner, like Magi-Klean, can get a seized pump working again.


There you have it. For everything you have invested in this hobby, these few steps are a small price to pay for a large measure of security. We love to help, but we would much rather you did not have to call because you were not prepared for an emergency. If you have any questions about preparing for aquarium emergencies, please contact us for support.

RELATED READING: Redundancies and Backups: 8 Ways to Prevent your Reef Tank from Crashing