Fluval 406 not moving any water?

[OliveFish05]

Hi there. We bought a 75 gallon tank with a Fluval 406. Got it home, cleaned everything, and set it up. The filter ran beautifully, really nice water movement, output, and filtration. Awesome. I do not have much experience with canisters, this is my first one. I watched a video and it seemed simple enough. We changed the output because we wanted it to match the black background, the former output was grey. Well not there’s no water flow. If there is any, it is minimal and barely anything. It was blasting before. I don’t know what I’m doing... I can hear it trying to run, it makes bubbly spurting noises every now and then.

 

[Oblio]

Been awhile since I had a canister, but it sounds like there is air in the impeller area. Most liquid pumps cannot pump air, which is why they need to be primed. Does the user manual specify how to get it primed, are your seals clean so air does not enter? I would not let it run 'dry' like that for long periods as the water both cools and lubricates the pump.

 

[OliveFish05]

Been awhile since I had a canister, but it sounds like there is air in the impeller area. Most liquid pumps cannot pump air, which is why they need to be primed. Does the user manual specify how to get it primed, are your seals clean so air does not enter? I would not let it run 'dry' like that for long periods as the water both cools and lubricates the pump.

Upon further inspection It’s not running dry, it is moving very, very small amounts of water. I just disassembled the entire thing, looked at everything, and put it back together. Nothing LOOKS “off” but I don’t know how I would know exactly. It’s like it’s slowed down, a lot. The seals all look great, the guy who owned it prior to us covered Anything that COULD leak in plumbers tape to be extra safe... it also didn’t come with a users manual as we bought it second hand with a used tank. I did prime it, there’s a little knob that you pull on and then push down A bunch until the bubbles stop coming... although the bubbles just keep coming. How would I seal off any area that air could be getting in?

 

[OliveFish05]

I’ve been sitting here doing the little knob for half an hour now... it’s running much better, not quite full speed, but better. There are still bubbles coming?

 

[Colin_T]

In my opinion, the priming feature on external canister filters are crap. Ignore them and do the following to prime an external canister filter.
Set the filter up and have the intake hose in the aquarium.
Have the outlet hose in a bucket next to the filter.
Suck on the outlet hose for a second to get water draining into the filter.
Put the end of the outlet hose in the bucket and let the filter fill up with water.
When water is flowing out of the outlet hose and into the bucket, put your thumb over the end of the outlet hose and put the hose in the tank. Secure it inside the aquarium.
Turn the filter on and when it is running, gently rock the filter case a few times to help dislodge any air bubbles.
The filter should work fine after that.

 

[Lajos_Detari]

Firstly, did you buy the same hose from Fluval for the output?
Make sure that you push both the AquaStop valve lever down.(see below)
One of the valve is to adjust/control the "water flow rate."

Also, make sure that the hose are not too long.
It must be straight and not looped around.
See below attachment and manual.

Secondly, did you replace the filter medias?
They could be clogged if you are reusing the old media.

If it's still not working, you can follow @Colin_T suggestions or check Fluval's website and the Youtube.


Fluval website. There are many tips here.
Scroll down the website:

https://fluvalaquatics.com/us/product/406-canister-filter/

Youtube:

 

[OliveFish05]

Alright, I think I figured it out (last week… I forgot to update) it’s running smoothly now! I’m doing a water change and noticed it’s got a decent flow rate.

 

[Lajos_Detari]

Are you having a double outlets for the output?
I haven't seen this before.

The one thing that I don't like is the intake and output hose which you can't see inside and is less flexible.
I prefer the transparent dark colour hose type.
Probably I will change the hose in future when they wear out.
Normal hose by JBL is cheaper than the Fluval hose.

By the way, I bought a Fluval filter in February but I haven't used it yet.
I was reading from a website to find out the most effective filter media.
According to the author, foam pad with 30ppi gives the biggest surface area for filtration and it's better than the ceramic rings, Biohome media, Seachem Matrix and other filter media.
But I can't verify the accuracy of his writings though I feel that he could be right.
Some info for you to read if you are interested.

7. Aquarium Filter Media

The media in an aquarium filter is the most important variable when setting up a filter.

aquariumscience.org

 

[OliveFish05]

Are you having a double outlets for the output?
I haven't seen this before.

The output house has two heads. The second hose you are seeing is the intake. When we bought it used, the hoses were too short to put the intake on one side of the tank and the output on the other.

The one thing that I don't like is the intake and output hose which you can't see inside and is less flexible.
I prefer the transparent dark colour hose type.
Probably I will change the hose in future when they wear out.
Normal hose by JBL is cheaper than the Fluval hose.

hmmm ok. That’s interesting , I will look into that! It seems like what’s on there now gets hard, not flexible at all really. It’s hard to work with!

By the way, I bought a Fluval filter in February but I haven't used it yet.
I was reading from a website to find out the most effective filter media.
According to the author, foam pad with 30ppi gives the biggest surface area for filtration and it's better than the ceramic rings, Biohome media, Seachem Matrix and other filter media.
But I can't verify the accuracy of his writings though I feel that he could be right.
Some info for you to read if you are interested.

7. Aquarium Filter Media

The media in an aquarium filter is the most important variable when setting up a filter.

aquariumscience.org

oh wow! I’ll look into that too. More surface area for bacteria? Yes please! Right now we’ve got whatever the company sells for it. We bought it used, and just decided to start off with that and look into better options once we got it home

 

[gilpi]

I have fluvals and sometimes (rarely) that happens, I shut it off wait a couple of seconds and plug it back in, it might take a couple of tries.

 

[Colin_T]

In my opinion, the best filter material/ media is sponges. They are cheap to buy, trap gunk, house beneficial bacteria, are easy to clean, and last for years. They also come in a range of sizes and are usually available in fine, medium and course grades.

 

[peony grace]

Firstly, did you buy the same hose from Fluval for the output?
Make sure that you push both the AquaStop valve lever down.(see below)
One of the valve is to adjust/control the "water flow rate."

Also, make sure that the hose are not too long.
It must be straight and not looped around.
See below attachment and manual.

Secondly, did you replace the filter medias?
They could be clogged if you are reusing the old media.

If it's still not working, you can follow @Colin_T suggestions or check Fluval's website and the Youtube.


Fluval website. There are many tips here.
Scroll down the website:

https://fluvalaquatics.com/us/product/406-canister-filter/

Youtube:

View attachment 156981


View attachment 156980


View attachment 156977View attachment 156978View attachment 156979

I just want to say thank you. I spent hours last night trying to figure out my new filter and was about to give up and run and get a sponge filter in the meantime. I decided to try one last time, and found your post, and voila! It works. I was so frustrated and helpless last night. God bless you and the internet.