Cleaning Canister Filters

Joel Armstrong

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What is your process/technique for cleaning canister filters?

How do you maintain the beneficial bacteria during cleaning?

And, how often do you clean them?


For me, when I clean my canister filters, I fill 2 containers with aquarium water. I pull out the media trays of seachem matrix from the canister and place them in one of the containers with aquarium water. I give the trays of matrix a slight jiggle in the container of aquarium water.

Then, I squeeze the sponges and filter floss in the second container of aquarium water, trying to dislodge as much muck as i can.

I then empty the canister of its remaining water, place the media trays back in to the canister filter and refill with tank water or dechlorinated tap water.

Is this basically the universal/accepted way of canister cleaning?


I am curious about your canister filter cleaning methods.
 
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I am running two Oase Biomaster 350’s and two Biomaster 850’s. I chose them because of the integrated heaters and prefilters, and they totally live up to expectation. I also have sponges on all my intakes which get squeezed once a week under the tap until clear. This keeps my canister prefilters good enough to only rinse out once a month. I squeeze the prefilter sponges under clorinated tap, as well, not worrying about the bacterial colony on them.

When I started with these filters I checked the canister media often and it was consistently so clean that I did nothing. Now I’ve settled into servicing the trays of media once every 4 months. I remove all the trays and usually just the fine sponge on the top is gunky, so it gets squeezed in a sink full of dechlorinated water. The canister water is dumped out, I stack the trays back in and refill with dechlorinated tap water. The media is out of the water for less than 10 min, so no worries about a bacterial die off.

This routine is so easy compared to years ago when I had large Eheims on a goldfish tank - it was a real chore to clean those filters and they needed it every week. I don’t think I would ever run a canister again without a prefilter, they literally take 3 min to pop out and rinse and keep the actual biomedia in the trays very clean for a long time.
 
I am running two Oase Biomaster 350’s and two Biomaster 850’s. I chose them because of the integrated heaters and prefilters, and they totally live up to expectation. I also have sponges on all my intakes which get squeezed once a week under the tap until clear. This keeps my canister prefilters good enough to only rinse out once a month. I squeeze the prefilter sponges under clorinated tap, as well, not worrying about the bacterial colony on them.

When I started with these filters I checked the canister media often and it was consistently so clean that I did nothing. Now I’ve settled into servicing the trays of media once every 4 months. I remove all the trays and usually just the fine sponge on the top is gunky, so it gets squeezed in a sink full of dechlorinated water. The canister water is dumped out, I stack the trays back in and refill with dechlorinated tap water. The media is out of the water for less than 10 min, so no worries about a bacterial die off.

This routine is so easy compared to years ago when I had large Eheims on a goldfish tank - it was a real chore to clean those filters and they needed it every week. I don’t think I would ever run a canister again without a prefilter, they literally take 3 min to pop out and rinse and keep the actual biomedia in the trays very clean for a long time.
Thank you for sharing your method
 
What is your process/technique for cleaning canister filters?

How do you maintain the beneficial bacteria during cleaning?

And, how often do you clean them?


For me, when I clean my canister filters, I fill 2 containers with aquarium water. I pull out the media trays of seachem matrix from the canister and place them in one of the containers with aquarium water. I give the trays of matrix a slight jiggle in the container of aquarium water.

Then, I squeeze the sponges and filter floss in the second container of aquarium water, trying to dislodge as much muck as i can.

I then empty the canister of its remaining water, place the media trays back in to the canister filter and refill with tank water or dechlorinated tap water.

Is this basically the universal/accepted way of canister cleaning?


I am curious about your canister filter cleaning methods.
I used this same exact method. However, lugging canisters grew old and went with the AIO with filter socks. I’ll either stay AIO or sump going forward as pulling a sock and washing it is a quality of life improvement I don’t see giving up.
 
I also have sponges on all my intakes which get squeezed once a week under the tap until clear. This keeps my canister prefilters good enough to only rinse out once a month. I squeeze the prefilter sponges under clorinated tap, as well, not worrying about the bacterial colony on them.
I am following same routine as @*Ci*

I try to remove as much organic waste from my tank as I can, and my prefilter does probably more than all other methods (soil vacuuming, water change, canister maintenance) combined. Same as @*Ci* I clean my prefilter weekly, and I am stunned how much black dirt I find in my white bathtub. I would say weekly from the prefilter not much less than I get from a monthly cleaning from my canister filter sponges.

After having tried several methods over the years, this is now my favourite (on a 1 inch FX4 intake).

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I’m pretty brutal with my filter cleaning I’ve come to believe that the nitrifying bacteria in the filter are way more resilient than we think or the bulk of the nitrification does not happen in the filter.

It’s usually every 2 months unless there is a reason to break the schedule.

Winter filter cleanings occur when my wife is at work or asleep, she would kill me if she saw what I did to the kitchen sink and washing machine. The large outer sponges get tossed right into the washer (no soap) and are replaced with the ones I cleaned the last time. I hose off the biomedia in the sink with warm tap water to get the worst of the goop off. Filter hosing gets dumped and hosed out as well. Summer time I do it with the hose in the driveway so it is not as much of a life threatening situation.
 
So, canister filter cleaning is probably my most hated chore in this hobby. So much so that, like @Unexpected, I switched to an AIO. MUCH easier to maintain.

IMO, the problems with most canister filters are:
  • Most don't factor in that mechanical filtration needs to be rinsed MUCH more often then the chemical and/or biological. If your canister filter doesn't have a pre-filter, then you are leaving your mechanical filter dirty for too long. This leads to a significant reduction in flow.
  • They are heavy and a pain to disconnect. Then you have to take them somewhere to rinse and clean. How much water do you get in your cabinet every time you disconnect your filter?
  • The biological portion shouldn't get dry while you clean them.
When I did have a canister filter, my process was similar to all of yours.
  1. Clean pre-filter and hoses weekly
  2. Clean canister every 6 months
    • Take to sink and remove the trays
    • Keep biological in old water and shake the material to remove sediment
    • Clean hoses and internal parts
    • Refill canister with chlorine-free water
    • Reinstall it and remind myself how much I disliked the procedure
 
I don't muck with cleaning with aquarium water anymore. I have a eheim 2227 and fx6; when i want to clean one i take it to the bath-tub; take the sponges out and clean them under running water for 10 or 15 mintues or however long it take to get most of the gunk out. I rinse off the bio-media blass or whatever you call the stone with tap water - and then i put the whole thing back together. I do not use water hot enough to burn my hands so we will call it warm. Same for sponge filters - take them to the sink and use tap water. Whether it is due to redundant filtration (all my aquariums have multiple sponge filters) or just that tap doesn't do enough harm to the bacteria i can't tell you but it works out fine.
 
I try to clean mine every two months but its often three. I use pillow floss instead of the sponges that come with them, dont have time to be rinsing 8-9 canister sponges. I get cheap $5 pillows from the dollar store or wal mart and use the stuffing. Then it's just throw the old away and pack it with new every time. Easy peasy
 
I try to clean mine every two months but its often three. I use pillow floss instead of the sponges that come with them, dont have time to be rinsing 8-9 canister sponges. I get cheap $5 pillows from the dollar store or wal mart and use the stuffing. Then it's just throw the old away and pack it with new every time. Easy peasy
Pro tip
 
There seems to be almost a consensus from experienced hobbyists, some with scientific background in water treatment, that micro organisms in the planted tank (plants, substrate, water column) take care of most, if not all biological filtration. The biological filtration role for the the canister is thought to be almost redundant. The view is also that high tech filter media are not much better than simple cheap media. We don't have measurement data (like ORP improvement versus time) for various filters and filter media, the only verifiable information is the price we pay for what we hope/believe will work.

I try to remove as much organic waste from my tank as I can, and my prefilter does probably more than all other methods (soil vacuuming, water change, canister maintenance) combined.
If assuming that it's mostly about mechanical filtration and removing organics from the system, a good strong circulation pump with a weekly cleaned prefilter may be a rational alternative (planted, not too much livestock, no need for carbon or other active media) to having a full canister under the pump.

I am in love with my FX4, but that's probably more from passion than from objective benefits.
 
Link

Took me a bit to find this one. I remember reading it a while ago when I first got canister filters. Immortal1 (rest in peace) did all the testing to compare Matrix with pumice. What I found most intesing was the nitrification results achieved with no biomedia or anything at all in the tank. Only the tank, filter, and hoses. Biofilm is everywhere and a pretty amazing adaption from evolution of bacteria. They survived millions of years dealing with worse than a little lack of oxygen or hot chlorinated water.
 
So, I don't want to derail the topic here (cleaning canisters), but I think filtration is an under discussed topic in our hobby. I do think that much of the products are marketing-led rather than science backed. I have also seen studies (unscientific) that show that sponges work much better than the pumice or pumice-like structure media. This is because the biofilm created by bacteria ends up clogging the pumice media so it isn't as effective.

For proper, long-term functioning of a biological filter, this biofilm needs to be kept to a minimum so that the bacteria can do their work.
 
Link

Took me a bit to find this one. I remember reading it a while ago when I first got canister filters. Immortal1 (rest in peace) did all the testing to compare Matrix with pumice. What I found most intesing was the nitrification results achieved with no biomedia or anything at all in the tank. Only the tank, filter, and hoses. Biofilm is everywhere and a pretty amazing adaption from evolution of bacteria. They survived millions of years dealing with worse than a little lack of oxygen or hot chlorinated water.
Am I reading your comment correct that 1) there was no superiority between matrix and pumice (I can believe that, they are pretty much the same thing in terms of surface porosity) and then separately 2) media had no impact on the nitrification process and that an empty filter circulating water seemed to be enough to have an impactful effect on nitrification?

Seems to make sense regarding no media since we do have filterless aquariums & ponds and rely on water changes only.

I do think we can make large improvements in filter media. I have some product ideas around that.
 
evolution-aqua-k1-media-sizing-1000__78953.jpg
This is K1 filter media. A couple of "studies" showed that this is one of the most efficient media for biological filtration next to certain sponges. The reason is that its design allows for water flow to slosh off the biofilm buildup thus giving bacteria more water contact time.

I'm currently using bags of these in my AIO. My unscientific observation, they are working well.

As to more or less efficient, I don't know.
 
Am I reading your comment correct that 1) there was no superiority between matrix and pumice (I can believe that, they are pretty much the same thing in terms of surface porosity) and then separately 2) media had no impact on the nitrification process and that an empty filter circulating water seemed to be enough to have an impactful effect on nitrification?
Yes this is correct in both points. Life will find away. Biggest take away is that bacteria are going to grow on anything and do not need ultra expensive bio-media. I use sponges and pot scrubbers. The sponges will get replaced with pot scrubbers when they wear out.

I think if you’re trying maximize nitrification and minimize space then the specialty media might come into play.
 
View attachment 3836
This is K1 filter media. A couple of "studies" showed that this is one of the most efficient media for biological filtration next to certain sponges. The reason is that its design allows for water flow to slosh off the biofilm buildup thus giving bacteria more water contact time.

I'm currently using bags of these in my AIO. My unscientific observation, they are working well.

As to more or less efficient, I don't know.
I’ve seen these frequently in my professional life. From air scrubbers to MBBR’s(moving bed biological reactors) in WWTP. They work very well for housing bacteria in a small foot print.
 
Link

Took me a bit to find this one. I remember reading it a while ago when I first got canister filters. Immortal1 (rest in peace) did all the testing to compare Matrix with pumice. What I found most intesing was the nitrification results achieved with no biomedia or anything at all in the tank. Only the tank, filter, and hoses. Biofilm is everywhere and a pretty amazing adaption from evolution of bacteria. They survived millions of years dealing with worse than a little lack of oxygen or hot chlorinated water.
Thank you for the link to this thread @FrankZ , it made my day yesterday reading from the first to the last post. One of the best threads I have seen.

When it comes to testing filter media, and theoretical predictions, the best reference that I know is

The author had a pretty robust test setup, and found that the most important predictor for effectiveness is the surface area where bacteria can find their home, and receive enough flow with nutrients and oxygen to thrive.

1703803306150.png
Then, from the assumption that it is the effective surface are that counts, some further comparisons are made that may or may not be reliable predictors for effectiveness as biological filter media

1703803535883.jpeg

Of course the question remains why we think we need biological filter media in a canister, as a planted tank probably can take care of ammonia and other waste without the help from a canister.
 
Cool thread.

Delving into the world of discus-keeping (a veritable cult, in some ways), the issue of water clarity seems to be enormously important. I currently have two primary setups - a 180 high-ish tech very densely planted tank with two Eheim classic 2217s. After 15 years in continuous service, I finally had to replace the ceramic shafts and impellors. Not bad, huh? The other tank is the discus setup, a 150g tank with a single enormous stainless 22 liter canister filter from AquaRocks.

The 180g has been up and running nonstop for over a decade. I usually clean out the Eheims every 4 or 5 months, but judging from what's in them, more frequently would probably be helpful. Like Art, it's a chore I really hate. Lugging the stupid things out from the cabinet isn't so easy, and it's a messy job. The water clarity of the 180 isn't great. This is probably due to decently heavy stocking (Kribs don't know about birth control) , really, really old substrate that isn't vacuumed all that often, and my laziness with cleaning the filters. The Eheims have a layer of ceramic noodles, two coarse filter pads, a layer of coco-puff ceramic balls, and a fine filter pad. They're pretty gunked up when they get cleaned.

As for what happens, I break everything down, rinse off the noodles and coco-puffs in lukewarm tap water (well water, no chlorine), wring out the filter pads until they're mostly clear, put it all back together, and reinstall. I usually do alternating filters every 2 or 3 months, or whenever the fancy strikes me. Flow is usually improved, but I can't say water clarity is any different before or after. It is astonishing how much mulm ends up in them.

For the 150g, I've only taken down the filter once, about 2 months after setup, and right before the discus went in. That one contains a mountain of ceramic media in media bags, several layers of open-cell coarse foam, and a layer of filter floss. Perhaps due to the enormous size of the filter, it really wasn't all that dirty at all. I'll break it down in a month or two to check on it again.

As for the science behind it, I have my own thoughts, but nothing concrete. The nitrifying bacteria that are oh-so-crucial to discus folks really aren't such a huge concern in decently planted tanks..... so mostly it's mechanical filtration I think. For our purposes, the biggest reason to have a filter is to remove suspended particulates, and only the reason to clean them in my mind is to maintain good flow.
 
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