This article is my opinion and advice about taking care of aquariums before and after a hurricane. This is based on my experience with two and half hurricanes in a two month period.
         
          First things first-if you have to leave the house, turn off the power at the main breaker box. Turn off the breakers when the power goes out during the storm if you are there (before the storm if the breakers are not in a safe place to be!). Unplug the lights/heaters/power filters. You do not want the power coming on unexpectedly and causing any short circuits or fires! If you have water coming out of the outlets after the storm, do not plug anything into them until an electrician checks it out. Sounds crazy, but houses leak in funny ways.
          Filters and air: Unplug any filters as soon as the power goes out (or before if evacuating) and make sure they are not siphoning onto the floor (especially canister types). Have on hand one battery operated pump with lots of extra batteries per tank. These pumps can be found at pet stores and any place that sells fishing equipment (they are used to keep bait alive). Also have on hand some sort of filter that is run via air stone-sponge, corner, and box filters work well. Do not forget to put an anti-siphon valve in the tubing-I found this out the hard way when during the second storm I lost a few gallons of water on the floor before I found out the problem! Your regular airlines should already have these installed. I put the filter into the tank before the storm came, and ran it in order to establish a colony of bacteria on it. Then, once the power went out, I switched the filter over to the battery operated pump. Both of the pumps I had were pretty noisy but not impossible to live with. The directions said the batteries would last 26 hours, but they usually went between 36-48 hours before changing them ("D" cell type). There are rechargeable batteries available, but if you do not have power to run your filters, you do not have power to recharge batteries! Other people tried using computer backups, but that seems an expensive way to do the same thing to me.. If you are lucky enough to have a generator, you could run your filters off of that. Generator current is not steady current though, and there is a chance of damaging your filter (or anything you run off a generator). It is important to keep the water moving, so even just an air stone without a filter will help. That way the water does not become stagnant, and anaerobic bacteria have fewer places to form. Keep the filter media wet with tank water; some of the "good" bacteria will carry over.
          Heaters: I live in Florida, so a heater was not an issue (especially without air conditioning in the house!). If you live in a hurricane prone area, chances are pretty good that the air temperature would be high enough to keep the tanks warm enough for the fish (except very sensitive species!). I was actually more concerned with the fish overheating, although the water temperature stayed within a reasonable range. You could run a heater off of a generator if you have one, but see the warning above.
          Light: Without electricity, there is no light. Chances are good that the windows are boarded up and the room will be completely black, so resist the temptation to shine the light into the tank to check on everyone- the sudden light will only stress the inhabitants and cause them to race around the tank. This is a good way to end up with injured fish! What I did was use a touch light to give a moderate glow near feeding time, and then I sat a flashlight upright (shining in) on the glass hood at feeding time. This avoided the sudden "lights on!", yet allowed the fish to see their food. Feed at or near their normal feeding times, and they will quickly figure out what is going on.
          Food: The best option is to not feed! Fish can go a couple of days without food (except very young fry, those must be fed daily!). I was without power for 10 days, so that option was not available. When I did start feeding, it was only flake food and small portions. I quickly found out that frozen brine shrimp and mysis shrimp fouled the water too fast (and with no freezer, they did not stay frozen anyway and went bad). The pelleted food for the catfish sat on the bottom, so I learned to only give one or two pellets. The algae wafers for the plecos also fouled the water quickly, so those were restricted to one wafer each fish. I fretted over my new Green Spotted puffer as he would not accept anything other than brine shrimp before that. After a few days with no food, he followed his tank mates' examples and is now an avid flake eater! If you have fish with specialized needs (tangs that need algae, for instance), try and wean them to at least accept some form of dry food. Watching your beloved fish survive the hurricane only to starve to death is not fun. If you have any frozen food, remove it from the freezer and discard it-when the power goes out it will be no good, and trust me-the smell will permeate the rest of your human food!
          Water changes: If you are lucky enough to be on city water and have running water, you may be able to do water changes. Be forewarned that if water mains break, the water can be contaminated. Without electric, sewage pumps do not work either and may overflow. After the hurricane, municipalities will run chemicals through the water mains to clean them out -test all water thoroughly and if in doubt, do not use it. You may not want to sacrifice your precious bottled water, but that is one option. The best thing to do is have lidded buckets filled with your usual water before the hurricane. Ask nicely at a bakery for their icing buckets! If you have a well, without power you will have no water- I have a well and used the prefilled buckets to do water changes. The less you have to mess with your tank though, the better.
          Alternate housing: I also raise turtles, and there was no way I could leave them in their tank for 10 days without cleaning it. I put them in separate buckets to facilitate water changes, but was running short on water. As luck would have it, my workplace had power and running water the next day. They were willing to turn a blind eye to a few extra "workers", and my turtles stayed in our break room. So if the conditions are too bad (or if your house is destroyed and your tanks are not), ask around - you may be able to move your fish to a temporary location until you get back to normal. Ask fish friends, even ask the boss if you can. Best if you ask before the storm however!
          Miscellaneous precautions: As my tanks are situated near windows, I placed a piece of plywood next to the tanks between the tank and the window in case anything came through the window. Even when the window was boarded up, I placed the wood there. I had a piece of plywood that was bolted into concrete pull out, concrete chunks and all, during the storm-do not think that the window is safe even shuttered! Shutters blow off easily also. If the tanks are moveable, move them away from windows and doors (doors blow open too!). I also covered the tanks with blankets in case the ceiling came down (or off.) in hopes that that might cushion the blow, and to keep any debris out of the tanks. Leaking roofs cause drop ceilings to sag and fall in, even if the roof stays on. That insulation and drywall would be hazardous in a fish tank. The blankets also were to keep the fish in the tank in case they started trying to jump out through the hood openings (see my paper on "Hurricanes and Nimbochromis venustus" for more on fish reactions). Make sure that the air pump has enough space around it.
          Plants: If you have live plants in your tank, and no power (hence no lights), remove them and place them in their own bucket of water. Plants compete with fish for oxygen in the darkness, and the last thing you want is any more oxygen being used. Be gentle when taking the plants out-some plants may not tolerate moving, and others may not grow for a while afterwards, but better dead plants than dead fish in my opinion.
          Moving your fish: I stayed near my house during the hurricanes, so I chose to keep the fish right where they were. If I lived in a trailer or on an island and had to evacuate, I would have taken the fish with me. I would have simply placed them into separate buckets (with lids!) full of their tank water. I keep a 10-gallon tank handy for quarantine, so I would have brought that and put them into it (would have been crowded!). I would have brought along their filters, media and all, and set them up immediately (keeping the media wet in a Ziploc bag). If bringing them were not an option, I would have simply left the fish in their tanks with the pumps running (see above for information on covering the tanks).
          To stress: unplug everything so that the sudden power surge does not cause any fires, check for any possible siphoning (check all filters and all air lines should have one-way valves installed in them!), protect the tank against breakage, feed very little, try not to stress the fish. If a tank breaks, watch for glass and any resulting mold from wet carpet (trust me it will mold!). Do not plug anything back in until you are sure it is safe.
          During the storm: Basically, all you can do is hope. Hope that your house stays in one piece, hope that the ceilings stay up, hope that the fish do not go crazy, hope that the power is restored quickly. As important as your fish may be to you (and me!), keep yourself safe above all! You can always find more fish, but you have to be around to do it.Do not try to go into the room if the windows break, stay in your safe room. Period!! Curiosity in this case can kill. Know that you prepared the best you can, and although it may take a while, the storm will end. Even the 36 hour long Hurricane Frances did end!
          After the storm: Once power is restored, do a partial water change. Keep and use the old filter media, if it stayed wet there is a good chance of bacteria surviving. My tanks only did a mini cycle, even after being without power for 10 days! Bring the fish back up to normal feeding levels over a few day period so they do not bloat. Check all equipment for damage, replace anything suspect. Remove any dead fish immediately and praise any survivors. Enough cannot be said about keeping tanks under stocked-over stocked tanks died out, while under-stocked tanks survived.