# When I lose power, my filters Flood my floors



## gunther (Nov 25, 2007)

I lost power this weekend for , four hours . l luckily noticed BOTH eheim cannister filters in both tanks 125 and 180 were leaking , I guess from back pressure or reverse flow.
Any suggestions to prevent this from happening again. :-?


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## kodyboy (Dec 9, 2007)

your canisters should not leak. The only thing that I can think of is the hoses are not properly attached or the canister seals are somehow incorrect, but they should have leaked to begin with not just when you power went out. That is very odd. I would turn them on and off and see what is actually happening then go from there.


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## lloyd (Aug 24, 2005)

hope this helps...recheck your tank and canister height differential, and the hose lengths you are using. there is a maximum suggested, for both of these specs, to limit the back pressure within the can. if you have loops in either line, i would suggest to cut them to fit. other than that, you might check the canister o-ring itself. a bend or dint there might also allow some slow drips.


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## srook23 (Feb 21, 2009)

I had a problem with my XP2 that I didn't get a good seal on it. It had actually been leaking a little for a good while before I noticed it...I would take it out and try to reseal it and try again...probably just didn't seal good.


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## tlspmm (Feb 1, 2009)

You might think about adding check valves to the tank return water supply. Reverse flow isn't a very nice thing when it's all over your floor. Check valves = no chance for water to go back from where it came. lol


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## JWerner2 (Jul 7, 2008)

Bottom line, cans shouldnt leak like that!

Check the main rings/seals. If the are off or not on correctly that is the only reason why a canister should flood no matter how much back pressure there is.

If the force from the back pressure is whats causing it then those are canisters I would never buy!


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## ddaquaria (Jan 3, 2004)

My pro models do that every now and then. When is the last time you replaced the main o-ring? I've gotten to the point that I only clean the filter about every quarter and I replace the o-ring after I test the old one (with careful observation and listing for air).


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## jschall (Apr 2, 2009)

When the pump is off and the canister filter is too low below the aquarium, the pressure of the siphon is too high for the main seal on the canister to handle.

If you can bring the filter up higher, it should help.


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## football mom (Feb 19, 2006)

I would think the canister should not leak at all unless the o-ring was bad.


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## jschall (Apr 2, 2009)

football mom said:


> I would think the canister should not leak at all unless the o-ring was bad.


Depends on the pressure. If the canister filter is 10ft+ below the tank, it's going to leak when the pump is off unless you epoxied the lid on or something.


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## mambee (Apr 13, 2003)

I keep my canisters in dish basins and check them for leaks whenever I clean them. The O-rings eventually dry out and have to be replaced.

Mike


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## tlspmm (Feb 1, 2009)

two words= Check Valves!! won't have this problem anymore!!


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## LSBoost (Jan 21, 2010)

Canister filter are seal tight with rubber gasket. If the installation of the canister is wrong or the seal is bad that's the only way that it will leak. There's not much back pressure from the tank to the canister.


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## fishEH (Sep 15, 2008)

Check valves will only work on the return lines. The canister intake line is designed to siphon water from the tank to the canister. Put a check valve on that line and the canister won't work properly. Tank pressure alone should NOT cause your canister to leak, regardless of tank height, IMO. I have two XP3's and have never had them leak. And I have a water line tied into the filter intakes for tank top offs. That means I've got house water pressure,about 50psi, running through my cans with no leaks. 
There's either a bad seal somewhere or a very poor design.


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## KaiserSousay (Nov 2, 2008)

tlspmm said:


> two words= Check Valves!! won't have this problem anymore!!


HereÃ¢â‚¬â„¢s a couple more;
Valve Failure
More still;
Compromised Seal
Still More;
Cracked Housing

Sorry couldnÃ¢â‚¬â„¢t` resist.
Check valves are known to leak, even the very expensive ones. 
Keeping your canister in a water proof container, as mentioned is your best defense against wet cabinets and floors.


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## moneygetter1 (Jan 8, 2006)

opcorn: I would chk the seals in both 'cans'. Usually first to go when failure occurs. "T"


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## MalawiAggression (Mar 12, 2009)

I have the same problem with my eheim 2224. From the similarity of replies, I assume mine must be an O-ring problem as well. It doesn't leak otherwise, and the top of the canister is less than 2 feet below the bottom of a 75G tank. There must be some serious pressure weighing down on that seal when the power is shut off, because water streams out around the O-ring.


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## areuben (Jul 17, 2003)

I would agree that it is most probably an o-ring in need of replacement - I would also add that it could be just that the o-ring needs cleaning. On a pro 2, the o-ring has a funky design rather than just a simple o-ring used in the classic series, or let's say a magnum. The pro-2 o-ring/seal gasket has several channels on the top and bottom as well as a concave center and this puppy needs to be properly cleaned and lubed. If you don't you should take it out (carefully, don't nick it) at every filter cleaning, clean the o-ring (I use a tooth brush) and any dirt particles on it, clean the o-ring channel (in the filter head where the o-ring sits) of any residue which will be there, and then lube the o-ring with an appropriate silicone or lube spray like the Eheim stuff. 99.9% these will rectify the problem. Your Eheim shouldn't leak. When you reinstall the filter, to check that you have been successful, plug it in and let it run for a minute or two and check for any leaking. Then unplug it and check again - usually this is when the leaking will occur and tell you that you need to redo the cleaning, reseat the gasket or the gasket is toast.


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