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Eheim Classic Canister   by Randy Ringstad

Information is provided with the autorization of Robert, owner of AquaBotanic.

My good friend Phyllis Ringstad was the owner and operator of True Aquarium Plants, a business she retired from just a few months ago; sadly, Phyl has now passed away, and will be greatly missed by her many friends. Her website was chockful of useful information, and one of the articles everyone remembers and misses is this one, the instructions for assembling and cleaning an Eheim Classic Canister. Phyl was kind enough to send them along to me, and this is just the way it appeared on Phyl's website. It's a lifesaver for anyone assembling an Eheim for the first time, and a good refresher course for anyone who has one!

One update: the Ehfifix and Ehfisynth layers are now supplied by Eheim as filter pads (the Ehfifix pad is blue, the Ehfisynth white), and should be placed in the filter in the same manner as shown in the diagram at the end of this article.


Congratulations, if you have just purchased one of the best filters around. At least this help sheet assumes that you did or will. You can put any filter media into the Eheim that suits your needs, but few will surpass the quality of the Eheim media. This sheet will help you get your new canister up and running in no time. This help sheet covers the Classic Canister (the cylindrical one). So, if you’re ready…

The Classic Canister Models:   2211–13–15–17–50–60

Okay, you’ve opened the box and scrutinized the filter, now it’s time to put it together. Grab the instruction sheet (it looks kind of like a folded roadmap) and check the parts list to make sure that everything is there. You may have to thumb through it a bit to find the English instructions but they’re in there. The instructions are very clear on assembling the filter so I won’t repeat it here. There are a couple of tips I can share with you that are not included in the instructions.

Table 1: Eheim Classic Canister Media Chart
Filter Media % Of Filter Volume Eheim Filter Filter Volume
EhfiSynth 10% 2211 1 Liter
EhfiSubstrat 55% 2213 3 Liters
EhfiFix 20% 2215 4 Liters
EhfiMech 15% 2217 6 Liters
    2250 12 Liters
    2260 18 Liters
  • 1. You first want to cut about three inches off of each size of tubing (if you have only one size of tubing, cut off two pieces the same size). These are the pieces that you’ll connect to stem on the top of the filter and the stem protruding from the lower side.
  • 2. Next, connect your double tap connectors to the hose pieces you just attached so that the valve handles point in different directions (one pointing up and one down). In the future, this will allow you easily reconnect the right hose to the right valve after you have disconnected it.
  • 3. With the double tap valves connected, attach the hoses to the other end of the valves (Don’t cut the hoses just yet. If you have one long hose don’t cut it in half to make two hoses, just attach both ends to the connectors for now.)
  • 4. Assemble the intake tube and strainer as the instructions say and place it where you want it on the aquarium. Do the same with the spray bar assembly. (Most European aquariums are 15 inches from front to back, so the spray bar will be too long if your aquarium is 12”. No problem. Use a hacksaw or sharp bread knife to cut the spray bar to the size you need. Don’t cut the end with the cap in it. The spray bar can run along the left or right side (pointing to the front of the tank). You can run the spray bar along the back wall of the tank but this will make the return pipe visible from the front.
  • 5. Once the spray bar assembly and the intake assembly are in place, you can cut the hoses to the right length. The tubing should be just short enough not to sag, and just long enough to allow you to be able to pull the filter out a little ways or move it from side to side a bit in the cabinet. When you connect the hoses to the intake and spray bar assemblies make sure to give yourself an extra inch or two to allow for the connection.

Filter Media

Now you’re ready for the filter media. Eheim recommends running the filter with floss and carbon for the first two weeks of a new aquarium to purify the water. This is a good idea, but optional. I’ll leave that decision up to you.

Your media kit should include EhfiMech, EhfiFix, EhfiSubstrat, and EhfiSynth. Now you need to know how much of each filter media to use. If you don’t like math there is a sticker inside the filter’s box that you can affix to the side of the canister that shows you how far to fill with each filter media. If you do like math, keep reading. You calculate the media’s proportion based on the filter’s volume. It’s not as hard as it sounds, just look at the charts below. *Remember to rinse out the EhfiMech and EhfiSubstrat before adding it to the filter. A spaghetti strainer or colander works nicely. Just rinse enough to get the dust off.

For example, let’s say that you have the Eheim 2213 Filter. It’s filter volume is 3 liters. EhfiMech goes in first and it should occupy 15% of the filter. 0.15 x 3 = 0.45 liter. The EhfiMech box holds 0.7 liter, therefore you need to use a little more than half of the box. EhfiFix should occupy the next 20%. 0.20 x 3 = 0.60 liter. But, wait a minute, the box of EhfiFix says 35 grams. You don’t have to convert grams to liters or any thing like that. The box is the same size as the 0.7-liter box so it’s safe to assume that it fills the same volume. Therefore, 0.6 liter is all but a little bit of it. So, tear a chunk off and save it - the rest goes in the filter. The amounts do not have to be that exact. Next is EhfiSubstrat at 55%. 0.55 x 3 = 1.65 liters. The box of EhfiSubstrat is 0.7 liter too. (Unless, you got the big 2.0 liter box.) Two boxes is 1.4 liters and that’s good enough. Add two boxes. Lastly, EhfiSynth is 10% of filter volume. 0.10 x 3 = 0.30 liter. Just like EhfiFix, the box is the same size as a 0.7 liter box. So, tear off less than half and put it on top of the other media inside the filter. Save the rest.

Now, follow the instructions on starting the siphon. When the filter is full of water, plug it in. For previous Fluval users, notice that the Eheim is a “no-burping-required” filter.

Meanwhile, three more months later…

By now it’s time to change out about one-half to two-thirds of the EhfiSubstrat biological filter media. EhfiSubstrat is made of sintered glass beads which makes it very porous, providing excellent surface area (18,335 sq. ft. / U.S. gallon) for nitrifying bacteria to thrive. The bacteria adhere to the glass better than any plastic or ceramic media. All this is why EhfiSubstrat is just about the best biological filter media on the market. However, even this will clog-up over time and need to be replaced. You only change out part of it so that the old media will seed the new media with bacteria without subjecting the fish to another cycle. The easiest way to do the change-out is as follows:

Call this The Second Half Maintenance

  • 1. Unplug the filter, close all the valves, and disconnect the filter.
  • 2. Drain the filter as you did for the quick maintenance above. (Leave out the bucket this time and let the water go down the drain.)
  • 3. When it’s empty, remove the lid and set it aside with the O-Ring. Now, lay out an old bath towel on the kitchen counter.
  • 4. Remove the EhfiSynth media (It will more than likely need to be replaced.) from the filter. Now, you want to pour the media slowly out of the canister into a row on the towel. The row should be in segments of EhfiSubstrat, a wad of EhfiFix, and EhfiMech.
  • 5. While the canister is empty, it’s a good time to rinse it out thoroughly in the sink with tap water. Do not use any chemical cleaners! Do not run it in the dishwasher!
  • 6. Set the canister upside down over the towel for a bit while you rinse out the EhfiMech (ceramic rings) just like you did when you first set up the filter. Afterwards, go ahead and put the EhfiMech back into the canister.
  • 7. Thoroughly rinse out the EhfiFix (green stuff or blue pad) in the sink and place it back into the filter.
  • 8. Since you’re rinsing stuff, why not rinse out the new EhfiSubstrat. Remember that this should be enough to replace ‡ to 2/3 of the original EhfiSubstrat.
  • 9. Now remove ‡ to 2/3 of the old EhfiSubstrat pile and throw it away (Ed. note: you can also boil the ehfisubstrat in water, with a splash of bleach if you want it to get nice and white again, dry and save for future use). Mix the remaining media with the new and place it into the filter.
  • 10. Put your EhfiSynth (white, cotton stuff or pad) on top.
  • 11. Now is a good time to clean the impeller.
  • 12. Wet the O-Ring, and slide it over the bottom of the lid and press down. Lock the clips into place, and reconnect the filter as you did before. The siphon should start by itself after you open the bottom valves and then the top valves. When it’s full, plug it in.
  • 13. Once it’s running again, give it a pat on the pump-head and say “See you in three months.”

And now…

Three months from this point, repeat “The First Half Maintenance” – the back flush of filter media. And three months after that repeat “The Second Half Maintenance” – EhfiSubstrat replacement. Notice that you’ve only replaced EhfiSubstrat and EhfiSynth. You don’t have to replace EhfiFix or EhfiMech until they are completely worn out. Just rinse and reuse. You may, at some point during the year, use some carbon for some reason or another. If you need to, place it in a convenient spot in the filter.

For example, you could exchange the EhfiSynth on top with it. Just remember that it doesn’t take long for the carbon to achieve the desired effect. So don’t leave it in too long. A couple of days to a week should suffice. If it doesn’t, then you need to have a look at your other maintenance practices.

For example, are you overfeeding the fish (very easy to do and the leading cause of fish death!)? Are you doing regular partial water changes. 25% every two weeks (recommended) or 50% every four weeks (that could be pushing it). Upkeep on these two factors alone may eliminate the need for carbon at all.

After the first year, you should check and see just how much it cost you to run your Eheim Filter. Then, compare that with what it would cost to run other types of filters. I think you be surprised at how much you saved in time and money.

Eheim Filter Media Model

This article: Copyright © 1998, True Aquarium Plants Reprinted With Permission