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How To Stop Your Fluval 406 Leaking!

The Fluval 406 is an extremely popular canister within the fish keeping hobby and although there are newer versions of the canister on the market these days, the Fluval 406 still has a huge user base of people who use it as their go to canister of choice.

Due to so many people using the Fluval 406, we often see people reaching out with a number of different questions about various problems that they are having with their 406.

One of the most common problems that people seem to have is with their Fluval 406 leaking and no matter what they try, they dont seem to be able to fix their leaking canister.

This is why we have decided to publish this article going over how you are able to stop your Fluval 406 leaking as we wanted to try and help as many of our readers as possible who may have a faulty Fluval 406.

Is It Normal For A Fluval 406 To Be Leaking?

The first thing that we want to cover is whether or not it is normal for a Fluval 406 to leak as this is something that we often see people wondering about.

Generally speaking, it is not actually normal for a Fluval 406 to leak and if your canister is leaking then there will be an underlying issue that is causing your canister to leak.

The most common reason that a Fluval 406 will start leaking is because of a cracked canister and this is actually something that is relatively common with some of the older Fluval 406 canisters so its definitely something that you want to keep an eye out for.

Why Does A Fluval 406 Leaking Leak?

A cracked canister is usually caused by either dropping your canister or by having something heavy fall on top of your canister and if you do have a cracked canister then it will start to leak.

Another common reason that your Fluval 406 may start leaking is because of an issue with the O-rings.

O-rings are what create the seal between the different parts of your canister and if these become damaged or worn down then it can cause your canister to start leaking.

If you have a leaking Fluval 406 then the first thing that you want to do is check your O-rings and see if they need to be replaced as this is usually the cause of a leaking canister.

O-rings can be replaced relatively easily and you should be able to find replacement O-rings at your local pet store or online with their price tag often being less than one dollar.

If your O-rings look fine but your canister is still leaking then it is likely that you have a cracked canister and in this case, you may need to replace your canister.

How Do You Stop A Canister Filter From Leaking?

The O-rings on your Fluval 406 are a core part of how the canister performs and with many of the Fluval 406 canisters out there being old and often not having had any maintenance done on them for a very long time, problems with their O-rings are very common.

Thankfully, there are plenty of replacements available online in the correct sizes that you require for your Fluval 406.

We would recommend that you order a replacement O-ring online as they tend to be cheaper than your local pet store while also offering a wider selection.

The actual replacement of the O-ring to fix your broken Fluval 406 is usually just a one for one O-ring replacement and in the vast majority of cases, there is no reason to use any lubricants or anything like that.

If your Fluval 406 canister is cracked then you may be able to fix the damage with resin but this is not beginner friendly and if you have never used resin before, we would never recommend that you try it as it can end up posing a larger risk to the performance of your Fluval 406.

If you are able to see a crack in your Fluval 406 then you should look at just replacing the canister as it will usually be much easier.

Thankfully though, the majority of problems with a Fluval 406 leaking is due to problems with the O-ring or the seals on the canister so they tend to be easier to fix.

If you think that the issue causing your Fluval 406 to leak is due to a seal then replacements are available online but they are slightly more expensive than a regular O-ring.

Fixing a damaged seal on your Fluval 406 is more complicated than replacing an O-ring but the manual have easy to follow instructions on replacing a set of damaged seals.