Eheim classic canister with barely any output?

I'm going through a bacterial bloom right now because I've added some spiderwood to my tank. The wood itself has developed a lot of that gross slimy bacteria/fungal growth, the kind of cloudy white/transparent stuff that sometimes happens with new wood. I've noticed that the output of my filter has slowed down significantly since, and my fish have been gasping at the surface because it's not providing enough surface agitation. I did a small water change today and checked on the canister, and it doesn't seem to be clogged or in need of a clean, but a lot of the media felt slimy.. when I plugged it back in it was just as slow as it was before. I'm a little concerned.. is it possible that the fungal filmy growth has gotten into my filter and that's what is slowing it down so much, or is this more likely to just be an issue with the filter itself?

 

I don't think the growth from you wood would clog the filter media, but perhaps could it block the intake or clog up the tubes. Have you checked these?

 

I don't think the growth from you wood would clog the filter media, but perhaps could it block the intake or clog up the tubes. Have you checked these?

Thanks for the suggestion, I've just checked both and they look clear to me, I don't see any blockages

 

Let the inlethose run in a bucket. You'll see if the inlet is enough.

 

If you've rinsed the media and cleaned out the hoses and connectors the only thing left to clean is the impeller and impeller well. I use an old toothbrush. Be gentle when handling the impeller shaft.

 

If the media didn't look clogged but felt slimy I can't imagine it would reduce flow. I would rinse it well in tank water anyway until it felt normal though just in case.

I'm the meantime have you got a spair air pump or powerhead knocking around you could rig up for a bit more oxygen and flow in the tank?

 

Let the inlethose run in a bucket. You'll see if the inlet is enough.

Thanks for the advice, but I'm not sure I know what you mean, could you elaborate on this?

If you've rinsed the media and cleaned out the hoses and connectors the only thing left to clean is the impeller and impeller well. I use an old toothbrush. Be gentle when handling the impeller shaft.

If the media didn't look clogged but felt slimy I can't imagine it would reduce flow. I would rinse it well in tank water anyway until it felt normal though just in case.

I'm the meantime have you got a spair air pump or powerhead knocking around you could rig up for a bit more oxygen and flow in the tank?

Thank you both for your suggestions. I cleaned the impeller when I rinsed the media - it was a little overdue for a cleaning, but the flow of water still has not improved.

Oh, don't worry about the air supply! I should have mentioned it in the original post, but I've got an airstone set up while I try and figure this out.

 

OK that's good you've got extra aeration going.

Have you added any extra media to the filter? The more its packed the lower the flow will be.

Other options could be some kind of airlock in the system

What flow rate is the filter rated for out of interest?

 

OK that's good you've got extra aeration going.

Have you added any extra media to the filter? The more its packed the lower the flow will be.

Other options could be some kind of airlock in the system

What flow rate is the filter rated for out of interest?

No, I haven't added any new media. It's the 2211 model, supposedly for 40 gallon tanks, I've got it in my 20ish gallon tank. 60 gallons per hour flow rate. I would've suspected an issue with air as well, but usually I hear a loud grinding sound if I haven't primed it correctly or there are bubbles..

 

So the 150 2211 model?

For up to 150 litres. Not sure if that's 40 gallons in the US but around there. Flow rate should be 300 litres per hour, minus a bit for media reducing flow. Not a strong flow filter anyway.

I think as was mentioned earlier.. If you put a bucket or measuring jug under the outlet pipe and see just how much is flowing? Maths could work out the flow rate.

Oh another thought. Is there any flow valves that may have been adjusted by accident? Was about to karate chop my canister when I set it up thinking air lock when I actually had a valve almost shut.

Is there any way you can get a replacement through eheim if its not working as intended? They have pretty good customer service if purchased new.

 

So the 150 2211 model?

For up to 150 litres. Not sure if that's 40 gallons in the US but around there. Flow rate should be 300 litres per hour, minus a bit for media reducing flow. That's pretty low flow anyway, I'd want more on a 20 gallon.

I think as was mentioned earlier.. If you put a bucket or measuring jug under the outlet pipe and see just how much is flowing? Maths could work out the flow rate.

Is there any way you can get a replacement through eheim if its not working as intended? They have pretty good customer service if purchased new.

Oh, I thought turning the tank over 3-4 times per hour was optimum? It's a planted tank that I usually use for housing quieter slow fish, so I didn't want it to be a very strong flow anyhow. I usually block the spray bar with frogbit to slow it down additionally because I find it to be too strong for the fish under normal circumstances.

Ah, I see what is meant now by DoubleDutch's suggestion to use a bucket! I'll have to give that a go when I get home and get back to you. I know eheim is really good at having spare parts available, but I don't know about the warranty. I'll have to look over the manual to see if it mentions anything.. see how difficult it will be to have it replaced.

 

Hmmm I think tank turn over rate opinions are very varied. Many say 10x per hour, many 5-6x or watever. It depends on your fishs requirements and stocking so if 3x works then it works.

Looking at the eheim classic filter is it possible there is somthing blocking the inlet part at the bottom? There is no filter baskets is there? Just wandering if some gunk could lodge somwhere.

Hope ya get it sorted anyway. Get stressed by filters myself.

 

Hmmm I think tank turn over rate opinions are very varied. Many say 10x per hour, many 5-6x or watever. It depends on your fishs requirements and stocking so if 3x works then it works.

Looking at the eheim classic filter is it possible there is somthing blocking the inlet part at the bottom? There is no filter baskets is there? Just wandering if some gunk could lodge somwhere.

Hope ya get it sorted anyway. Get stressed by filters myself.

Update! I was able to get my father to check. We only had a half gallon bucket on hand, but it seems it's currently pumping a half a US gallon approximately every 2 and half minutes, which is ridiculously slow. No filter basket, no inlet sponge, and it's not blocked up.

Not really sure what to do at this point except to take it all apart, clean everything as thoroughly as humanly possible and try again. If that doesn't work, I'm really hoping Eheim has a decent length warranty..

 

Thanks for the advice, but I'm not sure I know what you mean, could you elaborate on this?


Thank you both for your suggestions. I cleaned the impeller when I rinsed the media - it was a little overdue for a cleaning, but the flow of water still has not improved.

Oh, don't worry about the air supply! I should have mentioned it in the original post, but I've got an airstone set up while I try and figure this out.

Often the inlet hose is blocked by dirt.
If you detach the hose and make it run in a bucket you'll see if that is the case.