What to do

As I sit here in the SEQ storms...with no power for the last 11 hours I wonder how long my tanks life will survive. Only having a single battery operated air stone to create any kind of water movement in the system...

It got me thinking about what others may do or have in place to protect against these kind of unfortunate situations. May be a bit late for me now...but I would be keen to learn what others do.

Please share

So 11 hours has now turned into 27 hours......27 hours in a marine tank that consists of a sump and 2 display tanks - the sump being a biological and mechanical filter - full of life forms of all kinds, the 5 foot display tank being over populated to the Max.....

The second display tank consists of juvenile fish- the most delicate little critters you ever seen...

And none of it has any circulation, any lighting and no temperature control - I am led to believe the end is inevitable-

a sad end to much hard work and pride....

I had no idea that in this day and age that a electricity company that makes hundreds of millions of dollars -can't keep it going after a bit of wind - restore time I am told is 1-3pm 'tomorrow' almost 48 hours after the initial shut down.....

All I can do is

So far the only casualty is a little cromis but he fell victim to the banded shrimp taking advantage of the cover of dark.....

We had the power out for 32 hours and it took around a third of my over all tank life.

That was mainly because I took to long to put in ammo lock and PH buffer.

The room was dark so I couldn’t see the fish finding it hard to breath until I put our camping light in the room and could see what I had forgotten, so stupid!!!!!, I tell others to use it as quick as possible and forgot for 12 hours myself.

Well 32 hours passed without power -

No circulation pumps
No lighting
Sump had no flow /light
No feeding

A few interesting observations -

Ammonia rise and PH crash were my main concerns in such an over populated set of tanks - then the sump -Algae without flow and a heap of small life dieing can't be good or does it really matter?

Well in the 2 display tanks PH remained stable while Ammonia rose slightly .025 from nearly 0....

In the sump the opposite - PH rose to 8.9 though ammonia remained stable even after 32 hours......

Casualties- 1 chromis and a small patch of xynia

I was worried for the entire time and alternated the air stone between each tank- including the sump....about 2 hours each tank so it would be a maximum of 4 hours without some kind of air saturation-

Conclusion- our marine life is incredible, it has evolved over millions of years and has an amazing ability to adapt to some appauling conditions - I credit the survival to the large volume of waters in each tank along with the general good health of each tank prior to the power outage....its been 48 hours now and all is still going well, the impact on the corals is yet to be seen-they typically react slower so time will tell

They are still working on power for 18,000 houses. I am so lucky we didnt lose power here in Tweed, it does make me think of worst case scenarios. I am happy to offer free boarding for anything you are worried about losing. My 6 x 2 x 2.5 tank has a very low load and is coral frendly.

I've done a quick google and consolidated a couple of pointers and suggestions for easy reference, if anyone else could find any other information to add to this, please feel free to contribute.

First up, what happens during a power outage.

Changes which occur during a power outage

Oxygen depletion

One of the first things that happens when your power goes out is that the oxygen level in your tank begins to decrease. There are several things that speed the depletion of oxygen including:

- A heavy fish load
- Increasing temperature
- A heavy plant load
- Feeding the fish
- An increase in fish activity

Fish require oxygen, so if the tank is heavily stocked, moving some of the fish to a lightly stocked tank may help.

Plants will contribute oxygen to a tank when under direct lighting, but when darkness occurs, they begin using oxygen and releasing carbon dioxide. While covering a tank to decrease the light is a good idea for a fish-only tank, it may be more detrimental in a freshwater planted tank and a marine tank with lots of macro algae.

Fish can go for days without eating, so avoid feeding fish in a power outage because it will increase their activity level therefore increasing the bacterial activity causing an accelerated loss of oxygen.

Try to decrease the activity in the tank by darkening it with a sheet, etc. (unless you have a planted tank or marine tank with macro algae), and not disturbing the occupants. Quietly resting fish use less oxygen then active fish.

Consider having a battery operated pump/air stone or two on hand. While it will not replace your current air stone and pump, it will add some oxygen back into the water.

Change in temperature

After oxygen depletion, temperature fluctuations are the next most dangerous change in a power outage. Most well-insulated homes will maintain their temperature for several hours. Try to keep the temperature in the room as steady as possible. In cold weather, building a fire in the fireplace or draping a blanket over the tank to help insulate it may help. In severe cases, adding hot water or ice to the tank may be tried but realize that in a large tank, the amount of hot water or ice that will need to be added to significantly alter the temperature may be unreasonably large. Also, the sudden change in temperature as you add the water/ice, even if it is only several degrees, may be more stressful for the fish than the gradual temperature change due to the outage. Long power outages in very hot weather can be particularly deadly to a reef tank if the owner does not have a generator.

Once the power comes back on

When power is restored, be aware that the biological waste present in the tank and mechanical filtration pads may have started to be broken down anaerobically producing methane and hydrogen sulfide. These gasses can be very toxic to fish, so try to remove and clean the filter pads before the power comes back on. If the power outage lasted more than several hours, realize that your fish will be very stressed. Monitor them closely while disturbing them as little as possible for the first few days. If you see signs of ich or other diseases developing, take appropriate treatment action. Monitor the water quality as well and do not be afraid to do water changes to help get the water quality back to normal.


While a power outage can be a disaster for aquarium owners, it does not have to be. By taking a few precautions and buying some basic emergency equipment, you can protect your tank from the potential dangers of your next power outage.

Equipment to cope with a power outage

Common items that you should have, or probably already have:

Battery operated air pumps: available from most hardware/sporting goods stores, or online from various pet vendors. Don’t forget extra batteries. A battery operated air pump shouldn’t set you back more than ~$15, although there are ones that will automatically turn on in the event of a power failure that cost more. A battery operated air pump is invaluable, both for oxygenation and water movement, and they’re very efficient.

Uninterruptible Power Supplies: Often referred to simply as a UPS. Widely used in many homes and offices to prevent computer data loss during a power outage, a UPS will provide AC power from a battery for a limited amount of time. Very handy for periodically running pumps/filters/heaters, they can also be used to run low wattage air pumps for days or even weeks. Prices of UPS varies depending on the size of the battery in the unit. A useful investment, a UPS will be useful every day for protecting your computers and other sensitive electronics.

Less common items that will help in the event of a long term power outage (aka fun toys for men and other electronically inclined individuals):

Generator: gasoline or butane powered, a generator (depending upon the size and wattage) will anything from a small aquarium system to your entire house. Their downfall is they are expensive to run (especially with gas prices these days), require fuel (something that was in such short supply we usually couldn’t run one), are usually quite expensive and have to be run outside to prevent dangerous carbon monoxide buildup.

Portable power supply: these nifty items are usually sold for cars, and often have a built in jump-start capability, tire inflator, emergency radio, or some combination thereof. However, many also have AC plugs and function identically to a UPS. These cab be used to power a couple of small water pumps and it could be recharged via a solar charger.

Solar trickle charger: a small solar pane that trickle charges up to 12 volt batteries. Can be used to charge the portable power supply.

Automobile power inverter: Inverters of various wattages can be had in the automotive section of any department store, and prices varies depending upon the output wattage. Purchase one of the power converters that plug into a car cigarette lighter, then run an extension cord to your system. A small 4 cylinder vehicle won't burn too much gas idling and the system doesn't have to run all the time, just for a short period every hour.

Many of the above items, or combination thereof, can be used to charge D cell batteries for your air pumps, which is generally the most efficient use of your limited power.

Ammonia Neutralizers: like Seachem’s Prime or Kordon’s Amquel will go a long way towards keeping your fish alive by dosing Prime every day, and feeding very little. If your fish are still in the aquarium, refrain from feeding, and perform water changes frequently if necessary.

Fluorescent Lighting: not necessary for fish, but eventually necessary for photosynthetic animals. If your tank has lots of plants, macroalgae and coral, plugging in fluorescent lights into a battery backup for a few minutes to an hour a day can do wonders.

Power Back

The work doesn't end when you've got your power back! Take a few minutes to check your aquariums. Clean out the filters again, and perform another large water change. After that, you should be good to go!

Dendro - that is awesome info my brother

If i had that info prior to the outage I would have been able to at least keep the circulation pumps going via a cheap DC to AC converter...funny thing is I didn't even think of it - as obvious as it is.....got one now!

Great stuff mate - it confirms what I experienced, I was just lucky the deaths were low...

Thank you - Bruce would not only approve - he would be proud

Racist again, he is so nasty hey dendro,lol.

Well now that such a heavily stocked border line system has settled back into things even with a massive water change, the small but meaningful problems are doing their chain reaction thing.

I will loose around 90 percent of everything once the chain reaction has finished I would think.

The biggest issue is having them at the top of the system doesn’t protect the massive amounts of inverts in one tank.

Once it has settled down I am altering a few things and changing the inverts to the top tank, then I am getting a generator; the weather events are only going to get worse for sure.

We nearly lost hundreds of dollars in meats down stairs as well.

Its going to be one that will run all the hobby,plus a fridge,freezer tele and a couple of lights.

Oh well it was getting boring anyway, the dotty back was a huge loss though, I needed a few more months to get pics of the complete change of sex.

Its funny the clams down seem to give a rats and the my oldest corals bar one are fine??

No racism here - I feel the same about everybody equally....

The after effects are what do concern me now - I guess it will be a waiting game to see what is truly impacted....

Time will tell -

On a brighter note I hit the bar last night for a quick spin and the dirty water is only a small part of the bay - mainly the creek run off...will clear up in no time and we can get out again...

Racism? What are you talking about, we're all from the human race, lol.

Anyway, I think this would make a good sticky for the forum, only problem I see is that MOST of the measures described will work only if we are there when the power outage happens, as it would require setting up the portable pumps and such to the various alternative power sources. It would be great if there's a way that we can setup the backup system so that it will kick in automatically when there's a power outage, especially useful if we're taking a short holiday away from home.

Thoughts anyone?

Anything is possible -

It really will depend on you budget, solar charged deep cycle car battery on standby would last for years, and be something you could use as a temp measure for shorter outages, say 10- 24 hrs, this could be set to trigger in a mains outage and run your return pumps and maybe a small air stone to keep the critical stuff alive.

Better still a proper UPS will help run pumps with ease - they can be triggered to kick in when power goes out, you just need to run low current draw equipment if the outage is for extended times. The bonus of a UPS is they can protect gear from spikes and dips in power which will kill you electrical gear....

In my case a UPS of say 1000kva would be fine to run the main pumps for a few days, my main pump is only 24 watt and the tunze flow pumps use only 10-20watts - such gear would cost $600 to $1000 depending on the quality of the battery. This is gear that you really do get what you pay for.....though, second hand gear is available - just get the battery cells checked and you have piece of mind....and happy fish and corals...

Of course running lighting and chillers would be a challenge as they have high current draw- which just means they will run your battery flat quicker....as I said it depends on you budget.

There you go dendro,if you want to add anything more to it, its your thread in the advice section.

Everything in this section is locked so anything you want done just say so and its done.

Thanks for the info mate, every little bit helps build the advice section into all you need to know to get it right.

https://southeastqueenslandm.aforumfree.com/t1273-power-outage-for-reef-aquariumswhat-happens-and-what-should-you-do

I will put up what I find out on generators once I look in to them as well.

Once i finish the next level of my tanks now I know what the algae can do,I will need to protect it, so a generator will be a must.

I miss the dotty back , I had it to the stage where when I would lift it’s shell it would hide under and when it saw the net for photo time it just waited there,( like I am ready hurry up),it was very trained.


I went for a water change on the Monday at the end of cleve point on the sailing boat ramp and salinity was 1.012 by Tuesday it was 1.023,that’s the spot to always get reliable water no matter what, well nearly.

Thanks G, I'm hoping to find more details when I get some free time, and like I posted before, I'm really keen in setting up a system that will kick in when a power outage occurs without the need for manual intervention. Cost will be the main determining factor, but hey, we've already invested so much time, money and effort in our tanks, it only makes sense to put in a little more to ensure that it doesn't crash simply because of a little bad weather