# Aren't canister filters supposed to be water-tight?



## Gizmo (Dec 6, 2010)

Just got a Marineland Magnum 350 Canister Filter from Beverly (thanks!) for my 29 tall. Set it up with media, filled the canister to the water line, capped it and made sure the gaskets were seated and the clips were secure, then followed instructions in the manual to start it up...

Step one was to turn on the filter and then turn it off again once it buzzes, to allow the lines to charge and prime the pump. Step two was to turn the filter on once the lines were charged.

Turned the filter on and as the lines charged water kept jetting out around the lid. Turned it off, drained the lines, reseated the gasket, turned back on. THIS TIME I didn't turn it off again, just let the impeller cavitate until the lines charged and the impeller primed of its own accord. No more leaking, but there was also a 1/4" air gap between the top of the water level in the canister and the top of the canister.

Over the next week, water has slowly filled in that gap to the point that there's only a few millimeters of air between the gasket and the water level in the canister. The thing is completely silent. I've been checking for water dripping around the gasket, and have not felt or seen any.

Question 1: Are these things in fact water-tight? And if not, why?

Question 2: When I turn off the canister filter to overhaul it, how do I prevent it from leaking again?

Solution for the future: I bought some double valves with quick disconnects from PetsMart and they should be here next week. Next weekend I'm planning on siphoning enough water out of the tank that the canister inlet and outlet are out of the water, run the filter as dry as it will go, then turn it off and hope the lines drain before it leaks again. Fit the disconnects, and *hopefully* not have to worry about this anymore.

Thanks in advance for any thoughts...*i/d*


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## beaslbob (May 29, 2009)

nothing is 100% leap proof.

I have the cansiter filter also and similiar experiences.


My advice and most especially on a planted tank----Don't use filters. (other then the plants)

but that's just my .02


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## Gizmo (Dec 6, 2010)

beaslbob said:


> My advice and most especially on a planted tank----Don't use filters. (other then the plants)
> 
> but that's just my .02


As usual, haha.

Maybe it's just a security blanket for me at this point.


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## susankat (Nov 15, 2008)

Canisters are suppose to be water proof. I would say what had happened is the seal didn't seat right.


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## jrman83 (Jul 9, 2010)

Where do you plan to put the disconnects? I have them on my Eheim 2217. I put them at roughly half the distance of the line. I would not run that thing for one second if it were dry. Once you have the inlet line out of the water, I'd have it off. I have paid way too much money for the canisters I have to take a chance of damaging any seals or even coming close to causing excessive heat.


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## Rob72 (Apr 2, 2011)

i have a eheim 2217 and have no problems at it leaking or anything, you might not have the seal in correctly, they should not leak at all, like jrman said, i would not run it at all with no water in it, you can risk buring it up and they cost alot of money


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## Gizmo (Dec 6, 2010)

I have to put my entire body weight on top of the lid to get the thing to seat well enough that the clips aren't straining to hold it on.

I won't run it dry for more than a second. I just want to make sure the lines are mostly drained - the lines start to drain when the canister is 1/2 full.

I was planning on putting the disconnects maybe 1"-2" above the filter inlet and outlet - that way, when I cut off the water, it's a quick reach down to the switch on the canister.

The biggest reason I don't want it leaking is because the motor sits under the canister, and if water runs under there....I shudder to think what would happen.


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## jrman83 (Jul 9, 2010)

I think the reason you don't want it to leak is the same reason we all have. A good reason to keep your inlet somewhat high on the tank, but who ever does that?


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## majerah1 (Oct 29, 2010)

I noticed it did fill all the way up,which I was fine with.Never had a leak issue though.The O ring should still be in good shape,but for future references,look into getting one and a set of the other rings.I was told to replace them once you see any wear in them.

Im thinking the first time,you didnt have it seated just right.Any canister will spew like that if the lid or ring isnt seated properly.

In order to prevent the leaking,make sure to O ring(I think it was red?) is free of any debris,kinks,gaps and what not.Make sure its on the lid just right too.And when placing the lid on(you shouldnt need to apply all your weight to it,make sure the O ring is in the right place)Just mind where the notches are at and line them up and the inlet tube in the canister with the hole on the lid.It should be a tight fit but not that tight,lol.Im a woman and It didnt take that much for me to get it on there.


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## Gizmo (Dec 6, 2010)

Haha, well, women and men can usually accomplish the same things, men tend to get a little more pompous and bull-headed about it when they mess it up though.

Got my disconnects in the mail. Tonight I'll be breaking things down and installing them (hopefully). And I'm willing to bet that I did screw up in seating the gasket the first time around. Or maybe it needed to be wet to seat properly...either way, it's working now and I'm pleased as punch. *w3


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## majerah1 (Oct 29, 2010)

Glad to hear!


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