# How long can a filter 'survive' with no flow (power outage)?



## rebel

Hi guys, I am trying to answer the above question as it would related a typical canister filter.

I am keen to find any articles that show whether the ammonia oxidising bacteria can go dormant/survive anoxic periods and if so, for how long...

I already found one which gives good information on the potential for these bacteria to go into dormancy when ammonia levels are low.

http://onlinelibrary.wiley.com/doi/10.1111/j.1574-6941.2006.00170.x/full

Any comments and ideas appreciated.


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## PARAGUAY

Several hours in water then the biological degrades rapidly, a method used for taking fish to exhibitions shows etc is the filter media out of water in darkness, I will try and locate were I read this


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## foxfish

Yes Paraguay is right, the bacteria will die from lack of oxygen. The time it takes will depend on how long it takes to deplete the oxygen held in the water surrounding the filer media. You could prolong that time by removing the water & allowing some air to enter the canister but the media must be kept damp & dark.


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## ian_m

One Xmas holiday our estate had a "neutral" fault (neutral issue at sub station) which tripped everyone's whole house RCD on their consumer units for the whole estate. We were away and came back 3 days later, to fish tank at 18'C, freezing house and house alarm having just gone off after having its main battery go flat.

Anyway restored power, my e1501 JBL filter came on, heater came on and no fish or plant issues at all.


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## roadmaster

I do remember reading that the bacteria does not die off as quickly as I used to think, but cannot remember where I read it.(within the last year)
Oxygen depletion inside a sealed canister might happen more quickly than with a HOB type filter during power outage.
My concern would be with the organic matter trapped on/in the filter media and the subsequent fouling of the organic matter, and water therein in such a scenario.
Upon the filter returning to service the fouled matter/water, would be immediately  flushed back into the tank and could give rise to ammonia spike and or sudden algae bloom.
The latter would not be as much of a concern as the former with regards to fauna for me.


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## rebel

Thanks guys. I was wondering of the situation where the power goes off. The time to take deplete oxygen and damage the filter bacteria/archea etc. Assume that you can't remove the media because you are not at home.


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## alto

Most filters will be fine for several hours - this is where having a "clean" filter is an advantage, without the buildup of debris & co-existing (sludge) bacteria, there will be more oxygen available for bacteria of interest ... recently had a "planned" (given a few days notice) power outage from 8am - 5pm (or 6), I did set up battery air pumps on the tanks, but left filters 'As Is"; returned home to filters back online & tanks looking fine, fish all seemed happy & no negative impact observed
(note that ambient was  ~ 17 - 18C, & tanks usually run ~ 24 - 25C)


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## dw1305

Hi all, [





roadmaster said:


> I do remember reading that the bacteria does not die off as quickly as I used to think, but cannot remember where I read it.(within the last year)


Probably in <"Practical Fishkeeping: Think you know...">. 





roadmaster said:


> Oxygen depletion inside a sealed canister might happen more quickly than with a HOB type filter during power outage.





foxfish said:


> Yes Paraguay is right, the bacteria will die from lack of oxygen. The time it takes will depend on how long it takes to deplete the oxygen held in the water surrounding the filer media.


 Yes that's it. 





alto said:


> Most filters will be fine for several hours - this is where having a "clean" filter is an advantage, without the buildup of debris & co-existing (sludge) bacteria, there will be more oxygen available for bacteria of interest


Again same applies, if you use your filter as a syphon, or have very long intervals between cleaning you will have bulky organic matter in the filter that will feed heterotrophic bacteria that will deplete the available oxygen. I have _Asellus_ and MTS in my filters, they dispose of any organic matter but will contribute to the bioload.

If I lived in a location where power cuts were likely <"I would use a wet and dry trickle filter">, because they are very robust in terms of gas exchange.

Recent research has shown that in aquarium filters, across a range of pH levels, Archaea look to be the dominant ammonia oxidising organisms, (and the bacteria (_Nitrospira_) the organism responsible for the conversion of N02- to NO3-). As far as we know these Archaea are likely to be more tolerant of lower oxygen levels than nitrifying Bacteria.

This should be available <Mini review:<"Relative contribution of Archaea and bacteria to aerobic ammonia oxidation in the environment">.

cheers Darrel


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## Tim Harrison

Back in the day, I used to turn my filter off at night
My fish tank was in my bedroom and the filter was noisy and kept me awake otherwise.

No ill effects whatsoever...

Obviously, this is a practice frowned upon nowadays tho'
But I suppose it makes sense if the dominant filter bacteria are Archaea.
I'm also guessing that the bacterial community would eventually reflect my idiosyncrasy.


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## ian_m

Troi said:


> Obviously, this is a practice frowned upon nowadays tho'


Probably not. I did exactly the same, filter off in evening as tank was in the lounge, never suffered any water quality issues.

One problem I did encounter was the filter not restarting, especially of the impellor "was getting old", so eventually stopped turning filter off the evening.


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## GHNelson

Hi
Hibernation......you would be surprised what filters can do.....they can even induce mini white worm if given the correct parameters!
Had a plastic tub with newly received plants....never got round to planting them for about 4 weeks due to other issues...no heater no lights....just daylight!
Was running a Eheim internal filter....moved the tub and switched the filter on and it spewed out White worms ....true!
hoggie


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