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FAQs on Freshwater Filter Media

Related Articles: Know Your Filter Media, A Concise Guide to Your Options by Neale Monks, Freshwater Filtration, Power Filter Impressions,  A review of some popular mechanical filtration systems by Steven Pro,  Canister Filters By Steven Pro, Setting up a Freshwater Aquarium, Tips for Beginners

Related FAQs:  Biological Filtration, Establishing CyclingFW Sponge Filters, FW Canister Filters, FW Hang-on Filters, Ultraviolet Sterilizers,

Do marine pure biofilter media balls really work?    3/24/16

<Oh! http://www.cermedia.com/marinepure-products.php >
I have then in my freshwater aquarium for 3 months
I took one out no change looks like new.
I think it's a hokes there is no proof.
<Well; these products should "work" in time; as bio-films are made, they become populated.
Are you experiencing ammonia, nitrite, nitrite issues? Bob Fenner>
Re: re: marinepure.... More reading         3/25/16

I had and still have high a nitrate problem that's the only problem I have It did not change.
<Mmm; well; the "Cer" line will reduce (as in reduction; anaerobic) Nitrate; GIVEN enough volume of the media, a slow flow rate about it. Let's have you read here:
and the linked files above. BobF>
Re: Re: re: marinepure.... and more reading         3/25/16

There are so many freshwater aquarium filters
which one do you think is the best for a 20gal.goldfish aquarium?
<.... stop writing and start searching, reading on WWM. I'll look up for you one last time:

Filter media placement in HOB filter, FW  1/26/09 Hello WWM crew, <Hello Audra.> My 30 hexagon is a new tank that is about 80% cycled (no fish in it). It was used as a quarantine tank for 2 weeks before I moved the fish in it to their permanent home. My question is, in what order should I place the media in my AquaClear 70 filter? Instead of using the foam that comes with it, I'd like to use a flat filter pad. I understand these save space and work well to remove toxins and debris from the water. <Not all do, Polyfilters and some of the recent copies do.> I have to add crushed coral, carbon (when needed) and biological media. Is crushed coral considered a chemical media? <No, biological, maybe a mechanical in the right setting. You plan to put the crushed coral in the filter? If in the tank do consider a smaller grain media, the larger crushed coral ends up serving as a detritus collector, a nitrate factory.> I'm concerned about it being in the same filter with my bio media. There's not much surface space in the tank, so I hope my filter is an option. <Hmmm, any plans for a protein skimmer? This will help you out both with the aeration and filtration of this system.> Audra <Scott V.>

Re: Filter media placement in HOB filter...Scott V. actually getting it this time 1/27/09 Hi Scott V., thanks for the quick response. <Welcome....I guess.> The filter pad I'm using is a Polyfilter. My 30 gallon hexagon set-up consists of a bubble disk, small airstone, some plastic plants, the AquaClear 70 filter, and a sponge filter. Both filters are sufficient for 60+ gallon tanks. Aren't protein skimmers used in marine or saltwater tanks? I have freshwater. <Skimmers are for marine tanks, I do apologize. It does change things a bit. After answering so many marine queries you start to think everything has salt in it!> My PH is very hard but low alkaline, so the crushed coral is to buffer the water. <I see.> I've used it in the natural gravel before, but I didn't like the results. Can I place the media in my filter as follows: Polyfilter, crushed coral bag, carbon and then bio media? <Certainly.> I probably could put the bio media bag in the Penguin filter instead. Your thoughts? <Either could work, I would go whichever route forces more water through the media itself, not around it. Sorry again for the mix up, Scott V.>

Aquascaping and other Topics, rock, mech. and chem. filter media   12/31/09 Hello Crew, Hope all of you had a very merry Christmas and are preparing for a great New Year! I have a question on aquascaping, please. I have read that when using rock in the aquarium it is best to always use the same type and not mix them because it ruins the effect. <Mmm, can, but not always... or not necessarily. Have seen more than one size, texture, color in tanks, the wild....> I wanted your opinion as to whether or not it would be OK to use different colors of the same rock, such as red and white. <Sure> Also, in a power filter, please tell me what kind of mechanical filtration is best for trapping smaller particles without decreasing the water flow a great deal constantly. <Mmm... no "one answer" here... I like cheap "blue batting" from the yardage store, or the equivalent you can buy Dacron polyester labeled/packaged for fish tank use in a good deal of settings... but the re-use-able Ehfi- flockens from Eheim et al. are excellent in canister filters, the ceramic and sintered glass beads can be of use... even pre-packaged GACs....> The filter I have comes with sponges for this purpose but I have never used them and don't know how well they work. <Try them out> Also, I have seen sheets of padding that can be cut to any size that are supposed to work well, but have no experience with those either. <Are what many aquarium service co.s use...> And lastly, please tell me if you are familiar with the PuraPad and if so is it really as good as advertised? <Some folks have stated great satisfaction...> If so, would it make sense to use it along with Purigen or would that be overkill? As always, thanks for doing such a great job. James <I would just use one or the other... with the cautionary notes and rationale I've posted/archived on WWM. Bob Fenner>

What type of filter media should I use? (RMF, comments on Hexamita, carbon?)  7/13/08 I have been searching for many answers in your forum for the past few days, and I must say "thank you" for all of this information. I have answered most of my questions using the search. To explain myself, I would like to give a little background. <Ok.> A friend of mine moved out of the area and asked me to take his aquarium. There is one very large Oscar in a 35 gallon Hex aquarium with an Marineland Emperor 280 power filter. <Ah, first problem: the tank is _way_ too small for an Oscar, arguably even for a juvenile, let alone an adult. A tank twice this size would be much more reasonable. All cichlids are sensitive to dissolved metabolites -- that means ammonia, nitrite, and nitrate. So you need both good filtration (to deal with the nitrite and ammonia) and aquarium capacity to dilute the nitrate. Water changes of 25-50% per week are needed to further dilute the nitrate. Without this sort of regimen, cichlids are extremely prone to disease, especially Hexamita and Hole-in-the Head.> The Oscar started getting HITH disease even though I do weekly water changes and according to my LFS, all tests show very good water quality for this type of fish. <There you go. Am I good or what? The point here is that the tank is too small. While it is (theoretically) possible to keep cichlids in small tanks by doing massive (e.g., 90%) water changes on a daily basis, the only practical way to keep them as low-maintenance pets is to use a big tank so that water changes can be spaced out.> I read on your pages about Oscars that HITH may be caused by stress from the aquarium being too small, as well as the use of carbon. <Both these things have been cited in the past as possible triggers. But the balance of opinion nowadays relates HITH to the protozoan Hexamita, an organism that probably lives harmlessly enough in the digestive tracts of many aquarium fish, including cichlids. But when conditions decline, e.g., nitrate exceeds 20 mg/l, the fish's immune system stops working properly and the Protozoans can spread, causing harm. The precise symptoms depends on where the Protozoans end up, which is why Hexamita and HITH had been considered separate diseases for a long time. Both diseases fall under the category of "easy to prevent, difficult to cure".> My friend, and now myself, has always used Marineland Diamond Blend Filter Media in the Emperor 280's media basket'¦which is carbon and ammonia remover combined. <Not a huge fan of chemical media, either carbon or zeolite, in freshwater tanks. Neither serves much purpose when compared with the much bigger benefits obtained by doing large (50% weekly) water changes instead. Zeolite is doing something your filter bacteria is doing anyway, so is utterly redundant except in tanks (e.g., hospital tanks, sub-pH6 tanks) where it isn't possible to use biological filtration. In the past the theory was carbon removed dissolved organics from the water, letting you minimise water changes. When I started in the hobby, "old water" was recommended for freshwater fish, with aquarium books often suggesting 10-25% water changes a month as reasonable. Over time the dissolved organics made the water more acidic and gave it a yellow colour. If you do big, weekly water changes, none of this happens, so the carbon is redundant. Furthermore, to actually work properly, carbon needs to be replaced at least monthly, something hardly anyone in freshwater fishkeeping does. So all you get is carbon behaving as an (admittedly reasonably good) substrate for filter bacteria. Instead I would recommend using exclusively top-notch biological such as Siporax together with mechanical filter media that can be cleaned/replaced according to your budget. You should also have a filter offering not less than 6 times (and ideally 10 times) the volume of the tank in turnover per hour (irrespective of the "recommended aquarium" size offered by the manufacturer of said filter, as these assume best-case scenarios of tanks with small, clean fish like Neons).> I purchased a 75 gallon aquarium, and an additional Emperor 280 power filter. I plan to use both of the 280 filters on the 75 gallon. <These filters offer filtration of 280 gallons per hour each, and for your tank I'd recommend at least 450 gallons per hour total and ideally up to 750 gallons per hour. With big, messy fish -- the more the better. I am not wild about hang-on-the-back filters though because they don't seem to be as flexible as canister filters. I want filters that can have the inlet and outlet put where I want them, not limited by the design. I don't like filters that use proprietary "modules" either -- I want to be able to put whatever media I want in the filter. Hence I'd always recommend a decent canister filter such as the excellent value and highly reliable Eheim 2217. At about 260 gallons per hour, two of these would provide adequate filtration and three would provide excellent filtration. They are basically empty buckets into which you cram in whatever media you want. For an Oscar, a mix of sponges/filter wool for solid waste and then lots of ceramic noodles for biological filtration would be ideal. Eheim filters may be slightly more expensive than generic Chinese brands, but they last forever (or at least 10+ years) and such spare parts as you might need (like the rubber seals that will wear out after a while) are cheap and easy to obtain.> From the reading on your site, I have used water from the old aquarium in the new aquarium. <Makes absolutely no difference. The bacteria are not in the water column or even sitting on the gravel (much) but in the filter media. Unplug a mature filter from one tank and connect it to another tank with similar water chemistry, and you it will carry on working perfectly. You can also donate 50% of the media from a mature filter to a new filter to instantly cycle the new filter without causing any harm to the mature filter.> I also placed the new filter on the old aquarium in order to ready the new filter's bio-wheel. Since you do not recommend carbon in a freshwater aquarium, and this could be causing the HITH disease, what would you recommend I use in the filter media baskets? <As stated above.> Also, the Marineland "Rite-Size E" filter cartridges come packed with activated carbon. Should I slice these open and remove the carbon? <Nope. Just consider them money down the drain. Or at least that's how I view them. Activated carbon is a posh way of saying "charcoal", and a great way for manufacturers to sell you something at a premium that costs very little to make. These "filter cartridges" are overpriced for what they are anyway, and that just adds insult to injury. Over the long term, a plain vanilla canister filter into which you can add whatever media you choose will work out so much cheaper, as well as working MUCH MUCH better.> Thank you for all your help, Jay <Cheers, Neale.> <<I am in agreement. RMF>>

Re: What type of filter media should I use?  - 07/13/08 I understand what you are saying about filtration, but given my budget and what I have already spent, do you think the two Emperor 280's hanging on the back plus one Eheim 2217 (as you suggested as a good canister) would suffice for this 75 gallon with the one large Oscar? The 280s come with empty media chambers and I will pick up Siporax as you suggested to fill these with. The Eheim is 260gph and the two Emperor filters are 280 each. This would bring my turnover to approx 820gph (manufacturer spec). Thanks again, Jay <Hello Jay. What you propose should work. But you'd want to be clever about where you positioned all these filters to that they weren't all pumping water around just one end of the tank. With big aquaria, it's important to make sure the bottom of the tank receives lots of water current. So perhaps you'd arrange the Eheim so the spray bar pushes water downwards rather than forwards. Even better (and not expensively) you could couple the canister filter with an undergravel filter plate to create a "reverse flow undergravel" filter. This works by the filter pushing water into the filter plate via what would ordinarily be the uplift. The water then comes upwards through the gravel, further supporting nitrifying bacteria and incidentally also keep the gravel much cleaner than otherwise. While not much used nowadays, undergravel filters work amazingly well, and provide good water quality at low cost. A 75-gallon tank should work nicely for an Oscar (or a mated pair). Cheers, Neale.> Re: What type of filter media should I use?  - 07/13/08 Thank you for the quick responses and for the great information. I would have never thought about using an undergravel filter to create uplift. <Used to be very common during the 1980s, and much appreciated in tanks such as Mbuna systems where you want to combine good biological filtration with the chemical buffering provided by a calcareous substrate. Out of fashion nowadays because undergravels generally don't work with plants, and that's the direction advanced freshwater hobbyists tend to go.> The Emperor 280 filter's water intake tubes have a dual intake. I will have one at each end of the 75g aquarium, so water will be pulled into the filter from the bottom and middle of the tank and at both ends. Should I position the Eheim pickup in the middle of the aquarium near the water surface? <Without seeing these filters _in situ_ it's difficult to make any pronouncements here! But here's my test. Put individual flakes of food in the aquarium at different positions and depths. Watch the flakes drift around. If they move about constantly wherever you put the flake, then you're fine. If they collect in certain corners, then you have a "dead patch". If you find the flakes drift slower at some points than others, you have inconsistent water flow. In either case, review the position of the inlets/outlets and try again. As always, theory is fine, but actual experimentation is better!> Maybe even build a skimmer box that the Eheim pickup could pull water from in order to clean the water surface?? <Largely a waste in non-planted tanks. Surface skimmers are great for removing bits of leaves and such that float about. In non-planted tanks this isn't an issue. Rather, your problem is going to be faeces and uneaten food collecting on the substrate. Water changes will help (stir the gravel a bit each time) but my "tip of the day" is to buy a turkey baster. These are great for spot-cleaning waste in large tanks. Cheap and very effective. Also very useful for catching fry and separating eggs from mouthbrooding fish. No aquarist should be without one!> Your expertise is greatly appreciated. Thank you, Jay <Cheers, Neale.>

Cottonballs??? for filter media     2/23/08 Hello Neale!!!! How is everything going? It's been a while since I have talked to you:D. Anyway, I have a question (again). Is it okay to use cottonballs for your filter instead of the foam/sponge things you put into your filter to trap debris? Is it safe to use cottonballs? Thanks for your help once more. <Hello John. I'd think not; products like cotton balls are likely treated with bleaches and other chemicals to make them white. While harmless enough when dabbed on our skin, I have no idea if residual chemicals might leach out when placed in an aquarium for months at a time. In any case: sponges are better value, as a ceramic hoops, as these will last many years if properly cared for (i.e., rinsed off periodically). Hope this helps, Neale.> Thanks for your quick response again. <Cool. Cheers, Neale.>

pad... English... filter media maint.  12/5/07 hi guys I have a question . on my 140 gallon system I use Pura filtration pad by Magnavore I was wondering how often should I change them? thanks for all the help tom <Hi Tom. Please use capital letters next time you write. Since we use these FAQs to share information with others, anything you do to help in terms of clarity and legibility is appreciated. Anyway, these pads are supposed to be replaced every month, according to the manufacturers. Whether or not the relatively minor benefits these sorts of chemical filter media pads provide is cost effective will be your call. But I will make the point that in most freshwater tanks, 50%+ water changes every week will do at least as much good as things like carbon and nitrate removers for a merest fraction of the cost. Cheers, Neale.>

Storage of temporary Filter Media   12/5/07 Hi WWM crew, being new to this forum, like everybody before me, I truly would like to express my gratitude for what you do at WWM. It's an awesome source of information! I am going through planning a 40G Tanganyika Tank for smaller Sand Cichlids, so I am sure this will not be my last question. However I just still have to translate my questions from German... Anyway, tonight I was wondering if you guys have an advice how to store temporary filter media, like PhosGuard or Purigen? I'd like to run them from time to time as needed and confirmed by water testing, on my 10G planted tank and later the 40G. As these media are not that cheap and as I might not fully exhaust them in one run, I was hoping I could take them out of the filter and store them until the next time. What would be the procedure? Dry them? Keep them in tank water in a plastic bag? Would that kill the bacteria on it and actually create a problem next time the media gets tank exposure? Thank you Jörg <Guten Tag, Jörg! Chemical filter media, like nitrate and phosphate removers, can usually be stored dry. First dry them off (e.g., on a radiator) and then when dry place in a dust-proof container, such as Tupperware. Some can be recharged. If cost is an issue, then spending more money to get rechargeable brands of media might make sense in the long term. Here in England, water often has up to 50 mg/l nitrate out of the tap. This is too much of Tanganyikan cichlids. So using de-ionised water, or rainwater, suitably hardened is preferable. I use rainwater, and it is a very cheap and safe option. If you start off with low-nitrate, low-phosphate water to begin with, you may not need chemical filter media at all. When using chemical filter media in the 'polluted' water of Southern England, I find the cost/benefit ratio not at all favourable! You need A LOT of nitrate remover to make much difference! I hope this helps. Tchuess! Neale.>

Re: Storage of temporary Filter Media   12/5/07 Hi Neale, <Jörg,> thanks for your reply. I am in New York, and so far I've used a local brand bottled water (Poland Spring), which is very soft, very low KH as well. <Hmm... not ideal for Tanganyikans!> For the 10G planted + a couple of Tetras, fixing the water up to the right values is no problem. Cost is ok, too, as I don't need that much. As of now I've pH 7.0 / GH 7 dKH / KH 1.3 dKH / NH3 0mg / NO2 0mg / NO3 0.5mg. KH is really low, but as of my understanding it is difficult [impossible?] to raise KH without also raising pH as long as you don't use CO2, right? <Correct. In low KH aquaria, water chemistry (i.e. pH) stabilisation is best achieved using "soft water" buffers, typically based on phosphoric acid. Personally, I'd never keep any tank at less than 5 degrees KH unless there was an overwhelming reason to do so, e.g., I was breeding Apistogramma. Adding small amounts of crushed coral to the filter can be a cheap and effective way to add KH to the tank. It's a bit of trial-and-error, adding small amounts every week or two, and then seeing if it adds enough KH or not. The "goal" is to have enough to raise the KH to 5 degrees or so but not much higher.> And for the Tetras I even could have a lower pH (6.8?) <No real advantage. Fish don't really care about pH, except perhaps for things like sex ratios of fry. What they don't like are sudden changes or extremes (causes acidosis or alkalosis). Water hardness is much more relevant, because this is what impacts osmoregulation.> NH3 and NO2 are not "zero" I'm sure but my $6.99 test isn't any more precise... The Tap water seems clean as far as I can say, still have to do the NO3 there. Values are similar to the above, however GH is very low at about 1 dKH. KH is also very low, actually so low that I got the Salifert Test, as the El Cheapo Test, would barely show any KH. <I believe that this is typical of New York tap water.> I'll have a more detailed look into it when it comes to chlorine + phosphates + organic compounds. So far I think the water is a usable source, and I'm planning to do it "saltwater-style", having a 20G container ready, aerated and heated with the right values for the Tanganyika Tank. <Agreed; the water is nice and clean, and provided the aquarium contains lots of calcareous material, small water changes shouldn't cause major problems in terms of pH stability. Remember, Tanganyikan cichlids don't need huge amounts of hardness for the sake of hardness, but for the pH stability. You can mix your own Tanganyikan salts quite easily using cheap ingredients. Or you can buy them ready made.> Thanks again for your help and input, and greetings to England. Joerg <Cheers, Neale.>

Re: Storage of temporary Filter Media 12/5/07 Neale, thanks again for your quick reply. Will work on the KH. Oyster shells ok? Regards, Jörg <Yes. Smash them up with a hammer though: more fragments = more surface area exposed to the water = faster rate of dissolution = quicker elevation of the KH. Start cautiously, with maybe 1/2 cup of the stuff in the filter and see what happens. You may decide it is easier to fill up a big media bag of the stuff, place in a 5 gallon bucket, add water, and wait a week or two for the water to harden up naturally. You can then take water from there and add to the aquarium as required. Do have a read of these: http://www.wetwebmedia.com/FWSubWebIndex/fwph,alk.htm http://www.wetwebmedia.com/FWSubWebIndex/fwh2oquality.htm http://www.wetwebmedia.com/FWSubWebIndex/fwsoftness.htm Cheers, Neale.>

Siporax in power filter question, FW ap.      2/23/07 Crew- <Michael> I hope all is well. I'm writing today with a few questions regarding the placement of Siporax beads. Specifically, I'm setting up a 15-gallon freshwater dwarf puffer tank. I'm using an Aquaclear Mini (100 gph) for filtration. Inside the Aqua clear's media chamber, I'd like to place a Dacron bag filled with Siporax beads for their nitrification and denitrification benefits. <An excellent idea, proposition> I plan to cut the sponge in half to increase the volume of Siporax that I can place into the filter. I also plan on using Aqua clear's carbon insert in the media chamber (in between the sponge and the Siporax). My actual question regards exposing the Siporax bag to air when cleaning the filter. Will I be drastically harming the anaerobic population if I transfer the Dacron bag from the filter (through the air) to a small bowl filled with aquarium water (and then back when finished cleaning)? <Mmm, no... the majority of said anaerobes are located deep within the fractured areas of these sintered glass beads> I realize that the anaerobic colony resides in the anoxic "innards" of the beads (devoid of oxygen), but I have no idea if air will penetrate these regions during such a transfer. Any help is always greatly appreciated. Also, if you feel that my placement of media should be rearranged in any way (in terms of order), I value your advice. Thanks, Mike <Likely little issue here... I would avoid much in the way of rinsing such media... Bob Fenner>

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