What makes a canister hum more?

[Linwood]

I have four SunSun HW404B filters, and one Fluval 306.

I bought the Fluval first, and you can tell which ones I liked better.

However.

One of them... naturally the one in my office, is getting louder. Substantially louder -- from almost dead silent, to now being audible over my computer (which I sit next to), and actually audible from the next room if it is quite. It was nowhere near that noisy before.

I recently cleaned it thoroughly, including the impeller, added some lube, then finally replaced the shaft on it (ok, I broke it while cleaning it for a second time), cleaned the impeller, cleaned the impeller recess.

What makes a canister hum when it didn't before?

I've twisted it, shaken it (it's not air), made sure it is not resting on something that would amplify the noise like a cabinet side. The noise is mostly hum, not water movement.

I've never opened the casing for the motor itself (not even sure if one can, I know some pumps are encased in epoxy for safety reasons, have not looked). Not sure if there's anything that can become loose in it.

I've turned off the UV light (in case it was a separate transformer to power it) and no impact.

So what makes a canister hum? And any suggestions, other than swapping it out. I may swap for one in another room, though I kind of hate to move the noise there either.

 

[Linwood]

Incidentally the change came over a period of about 9 months, slowly. It was not "break" where suddenly it was loud. It just got worse.

 

[Delapool]

Sounds pretty clean!

Assuming there is good water flow from the outlet still? That's all I can think of is if the water flow is getting blocked, the pump will be under pressure and could hum more.

 

[Linwood]

Yeah, good flow, in fact after cleaning (it was pretty awful) the flow went way up, but no change in noise. If I stop the flow, I get a fair amount of clacking as you might expect, but this is more of a hum. Though since the rotation is synced with the 60 cycle current noise in the rotation may sound similar to a hum, so it's hard to tell.

I think Iv'e got a spare impeller. This (of the five canisters I have) is by far the hardest to get to -- naturally -- so when I get ambitious will take it out and swap impellers and see if it makes a difference. I know it wasn't broken, but maybe it's warped slightly or something similar. Short of disassembling the case not sure what else I can do, but it might be time for a different one.

 

[54seaweed]

I have seen canisters hum from being over full with water and also under full they are very temperamental , if water level isn't just right they tend to be loud I would use that hum to your advantage , knowing canister needs attention

 

[Linwood]

I have seen canisters hum from being over full with water and also under full they are very temperamental , if water level isn't just right they tend to be loud I would use that hum to your advantage , knowing canister needs attention

I'm sorry, I thought a canister was by definition completely full if it didn't have air in it. Can you elaborate a bit on what "over full" means in this context, and how I might check?

 

[54seaweed]

most canisters have water level marks stamped into the plastic on inside of canister ,
the one I have has 3 marks low , min , and max any other levels tend to cause the pump to hum , the wet dry canister I have looks like a computer CPU , and is one of the best I've ever used I'll get a pict in a few min and attach to this same post

Ok here's 2 picts I keep mine in a 30g tank that is also utilized as a ATO
my canister is marked in marker so I see levels since it's in a tank I can't see the stamped marks on trays inside canister
I'm in cleaning mode but you'll get the idea
both side view and top view

 

[Linwood]

That's.... different. In this one, the pump is actually at the top. Until the media area fills and actually over-fills, the pump is dry. I don't think this one works the same way as what you have (nor does the Fluval).

 

[54seaweed]

just added picts to post #7

 

[Linwood]

Interesting. Is this more like a sump, where it's open to the air on top? The canisters I've seen are sealed, water coming in via one tube and out by another, no air inside at all.

 

[54seaweed]

kind of like a sump it's got a sealed cover , the cover is off at moment as I'm doing cleaning ,

 

[Delapool]

kind of like a sump it's got a sealed cover , the cover is off at moment as I'm doing cleaning ,

Following to learn something

Would you have a link on these? I'm not sure I'm picturing it right?

Copied the link of the larger canister I have below. Just a motor on top and a bucket of media trays underneath.

https://www.amazingamazon.com.au/aqua-one-nautilus-2700-canister-filter.html

 

[Delapool]

Interesting. Is this more like a sump, where it's open to the air on top? The canisters I've seen are sealed, water coming in via one tube and out by another, no air inside at all.

Could you put a cane basket over the canister or something to reduce noise? Mine sits in a cupboard under tank and that does cut down on the humming sound.

 

[Linwood]

Delapool, I could probably put a blanket over it, nothing more structured, it's really crammed into a corner now beside some cabinets (the hoses run sideways to the tank 4' away).

But... hmm... maybe a blanket. Never considered that, but I don't see a need for air circulation around it. Worst case it gets a bit warmer and the heater does less work.

Let me see what I can find.

Still begs the question why it got worse!

 

[54seaweed]

Following to learn something

Would you have a link on these? I'm not sure I'm picturing it right?

Copied the link of the larger canister I have below. Just a motor on top and a bucket of media trays underneath.

https://www.amazingamazon.com.au/aqua-one-nautilus-2700-canister-filter.html

if you didn't know better you would think it was a computer cpu lol

I love this thing it does everything a sump does plus some
the only modification I did was add a 1/4 hp pump to replace 1/8 hp pump

it's self contained it houses a skimmer ,both the return pump and skimmer pump , has a compartment for either a heater of a uv sterilizer ,I have heater , it has 3 trays 1st has filter media 2nd has live rock rubble 3rd has phosban socks , the very top has a algae scruber , I had a ATO unit till it sprung a leak , now I use a 30g tank that the filter sits in filled 1/2 way it adds water as its needed millions of pods in my canister that feeds main tank works way better than the sump I replaced with this
I have nothing but good things to say about this thing
Aquarium Filtration: Rapids Pro Series Wet/Dry Filter from Tom Aquarium Products
it also comes with a hob overflow