# Fluval 406 Issue - Clamps not tight on canister



## wzarektah (Mar 11, 2017)

Recently purchased a Fluval 406 to run with my existing 405.

After a few weeks I noticed the 406 was intermittently blowing micro bubbles every few minutes. I also noticed the gap between the motor head and the canister was much larger than the gap on my 405, which basically clamps down perfectly tight. The 406 seems to be taking in air from this gap. I also noticed the clamps do not close tightly to the canister on the 406 like they do on the 405 which makes me concerned that it may leak if the o-ring fails.

I called customer service and they told me the clamps aren't supposed to be tight, but that doesn't seem to make sense to me. I would think the clamps should be tight to help prevent water leaking and air intake into the canister. If I push down on the motor head to help create a good seal to the canister and then apply the clamps, it is very clear the clamps are doing virtually nothing.

As a quick fix, I put some air tubing under the area where the clamps grip to make them clamp down tighter. Not a long term solution...

Anyone else out there with a 406 have the same issue or do I just have a defective product?


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## wzarektah (Mar 11, 2017)

Bump...

Nobody on this forum has a Fluval 406 and can share their experience?


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## nodima (Oct 3, 2002)

I no longer run fluval filters, after my issues with the 04 series. If I were in your shoes, I'd try a replacement O Ring. The clamps as I recall did not take much pressure to close/latch. Is this filter brand new?

Can you provide some pictures to help us see what you are experiencing? That will be quite helpful.


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## BlueSunshine (Jul 13, 2014)

We've been running 2 406's for about 3 years. The clamps have never been tight. Sounds like you have a seal that has gone bad and allowing air to be sucked in.
Going to the manufacturer was a good start, just don't get mad when they do not tell you what you want to hear.


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## wzarektah (Mar 11, 2017)

Thanks for the replies.

So Hagen has offered to send me a new filter as soon as I send them my old one. After I complained about having to pay for shipping back a defective product, they offered to pay for the shipping. Should take 7-10 days to get my new filter and they receive the defective one.


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## bignaz (4 mo ago)

i have the same issue on a 305. i cut some zip strips (approx 1"x4) and glued them to the canister where the clamps make contact with it. i did replace the seal and the motor head just won't close tight on one side with the old seal or new. good thing i noticed it or it would have leaked into the basement and ruin my ceiling tiles and damaging my tank cabinet. i can't tell if the clamps are worn at the contact points or the canister lip is worn/damaged. its working now but i do have a sunsun back up filter.


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