Mayday! Mayday!! Filter Not Working!! Help

Discussion in 'Filters and Filtration' started by oOturquoiseOo, Apr 21, 2018.

  1. oOturquoiseOoWell Known MemberMember

    I just did a water change and I had to unplug the filter to do it. When the filter was plugged back in it makes a noise but it doesn't move any water.

    It is a fluval 406 canister filter. I took it apart and cleaned everything in old tank water but I can't see any of the mechanics so I can't see what's going on.

    It still isn't working
  2. SwampgorillaValued MemberMember

    It probably just needs to be re-primed.

    You have to evacuate all the air from the canister and the input line before it'll work properly.

  3. oOturquoiseOoWell Known MemberMember

    Thank you but I've done that

  4. BabaWell Known MemberMember

    Does the impeller move freely? Maybe the axle slipped out of a bearing

  5. SwampgorillaValued MemberMember

    Are you sure? Do you have another pump to force water through the filter from the tank?

    Well ... if you are sure ...

    Not familiar with the Fluval 406 ... I'm only familiar with the cheap Chinese canisters ... but why can't you see, as you say ... "the mechanics"?

    The "mechanics" should only consist of a magnetic drive motor and an impeller. I usually "bump" mine ... that is, before I put my canisters back together I look at the impeller and plug the motor in for a half second to ensure it's turning.
  6. oOturquoiseOoWell Known MemberMember

    The filter has a priming pump in it. I dumped all the old water when I cleaned the filter and when I reattached the hoses I primed the filter and it filled with water.

    In the lid everything is enclosed. I have to go out now for about a half hour, when I come back I'll take it apart again and hopefully I'll be able to figure something out.

    I gave it a few bumps hoping to start the impeller moving but it hasn't helped yet.

    I have a sponge filter in there too so it should be ok for a little bit. And the filter is filled with fresh tank water from the cleaning. I'm hoping I can figure it out before the bb start to die in the filter
  7. TexasDomerFishlore LegendMember

    Are you starting it from empty, or are you filling the canister all the way before turning it back on?
  8. SwampgorillaValued MemberMember

    You mean to tell me the MIGHTY FLUVAL 406 (which costs around $200 bucks) is designed where you can't easily see the impeller??? Someone please dispel this notion for me!

    Well, I wouldn't leave your canister for 30 minutes ... you're going to start losing bacteria due to lack of O2. Better plan would be to remove the biomedia ... submerge it in tank water ... while running a sponge filter for aeration. And even then, I'd say some "Hail Mary's" hoping for the bacteria to survive.

    EDIT: I still think you're not primed. Look at the timing ... the thing stopped working when you did a water change. It's not uncommon to lose prime during a water change if you go below the intake of the filter. Everything was fine until you changed water ... that's the galvanizing event here. Most filters these days have a priming system on them - but check the forums and you'll see plenty of people have problems with them.

    Perhaps even with the Fluval 406.
  9. TexasDomerFishlore LegendMember

    I have the 405 (older model of 406) and I can easily see and remove the impeller. I'm pretty sure that you can access the impeller through the bottom of the lid of the canister in the 406 too.
  10. oOturquoiseOoWell Known MemberMember

    I have been told in this forum that a 4 hour power cut wouldn't cause too much damage to the bb. I'm going to assume that the bb will survive long enough for me to go let my mom's dog out.

    Generally a water change takes me upwards to 1 hour because I have to lug buckets of water.
  11. SwampgorillaValued MemberMember

    When you unplugged the filter for the water change - did you also close the inlet and outlet valves to the canister?

    What I do is put my "inlets" way down on the bottom. I can do up to a 70 percent water change and never have to turn off the filters.
  12. oOturquoiseOoWell Known MemberMember

    I filled it by priming it and filling it with tank water. Then I wiggled it a bunch to get the rest of the air out. Then I plugged it it.
  13. oOturquoiseOoWell Known MemberMember

    I'm back now. Going to pull the filter apart again now if the kids cooperate.
  14. oOturquoiseOoWell Known MemberMember


    I took it apart again and it was full of water. I plugged it in with the top off and wouldn't you know the thing is working now?!


    Thank you all for trying to help.

    Ps, I can't leave the filter going while doing a water change because the water coming out of the output splashes everywhere and makes a huge mess. I can't put the outlet further down into the water because the hose is fixed in place. 2a2742f178de0fc64b2e596f303436b2.jpgc51c636aa47928416463559a58e8c943.jpgc733490a809e64895738ed2b914a9a1f.jpg
  15. TexasDomerFishlore LegendMember

    The impeller is under the cover in the second pic.

    Sometimes you need to prime it after it's plugged in, not just before you plug it in.
  16. oOturquoiseOoWell Known MemberMember

    Thank you. I know where it is but I can't seem to get it open.

    I promise I tried it all. I primed it and waited for all the bubbles to stop. Then I wiggled and banged it and more bubbles came out. Then I plugged it in and tried to prime it again, wiggled it again, and banged it again. I'm sure the impeller just wasn't moving. I don't know if maybe the suction of taking the top off again might have pulled some water through it and unstuck it.
  17. TexasDomerFishlore LegendMember

    You can take the cover off by pulling back on one of the pieces on the side of the cover. I promise it'll come off.
  18. oOturquoiseOoWell Known MemberMember

    Thank you. I'm just nervous I will break it. Next time I do a water change I'll watch a video about it and take it apart just to be sure nothing is caught in there
  19. SwampgorillaValued MemberMember

    Well you said it was making noise but not pumping? Usually that's a sign of lack of prime - the noise is usually the impeller turning. Anyway - you check for a stuck impeller simply by plugging it in real fast while looking down at the impeller to see if it turns.

    It really only takes a small amount of air to keep a canister from priming.

    Another trick ... take a small submersible pump and blow water from the tank through the inlet of the canister - through the canister ... to the outlet in the tank. Run it for a few minutes, then turn on the motor and see if the canister keeps pumping water. The submersible pump will usually blow any air out of the system.

    Also - that submersible pump ... you can use that to do water changes rather than lugging buckets. Just get a huge rubbermaid trash can fill it up with water, treat it for chlorine ... and fill your tank up. You can also pump the water out of your tank with the pump. These pumps cost less than $20 in most cases.

    As far as having to turn the canister off for water changes ... you can redesign the outlet if it's too high in the tank, and extend it down. You don't have to live with what Fluval gave you. On just about all my filters - I have modified the in and the out on them.
  20. oOturquoiseOoWell Known MemberMember

    Thank you.

    I feel like I need some agitation at the surface of the water for gas exchange. Maybe I'm being silly about.

    I generally prefer a spray bar but the store didn't have one when I bought the filter and I kind of just forgot about it because the output gives the water lots of movement and all the fish seem happy.

    Magically my son actually found the information booklet that came with the filter this afternoon. I will read it over again to figure out how to open the piece over the impeller

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