(3) Sponge Material Used
(5) Use (Air Pump or Power Head Methods)
(6) Additional Sponge Filters for Small Aquarium, Bowls
(7) Additional Sponge Filters for Breeding or Large Aquarium
(9) UV Sterilizer/Sponge Filter Combinations
(10) Sponge Pre-Filters
(11) Other uses of Sponge Filters (Sump, etc.)
(12) Media Care
Sponge filtration is an often overlooked type of filtration for both large and small freshwater tanks and bowls, and even ponds or marine aquariums. Many aquarists look past these filters because of their simplicity, but therein lies their quality.
I have used these filters for my aquarium maintenance business for 32 plus years with excellent results in freshwater, saltwater and ponds.
(The picture to the left is a Hydro Sponge #1 in a 6 x 6 x 6 Betta tank.)
The best sponge filters (such as the Patented Hydro Sponge Filters) can be used to compliment another filter, such as a power "hang on back" (HOB) or canister filter, or even as a stand alone filter, as per our extensive controlled tests. We found that only fluidized sand bed filters out perform sponge filters for aerobic bio filtration.
In fact I, and many other aquarium professionals, have used sponge filters as the only source of aquarium filtration.
With this in mind, people purchasing one of the many 'Aquarium Kits' sold at Walmart and elsewhere would be much better off with a superior bio-filtration such as our Sponge Filter Kit instead.
As a bio filter, most premium sponge filters (such as our Premium Hydro Sponge Filter) are vastly superior to Under Gravel Filters as per extensive controlled tests performed by us in the 1990s.
This is due to the very porous nature of a sponge filter that allows for extensive colonization of nitrifying bacteria, assuming your aquarium or pond is adequately circulated.
Please note that many "knock off" sponge filters made by a variety of brands (such as Lees, Tetra, SF-XY, AquaTop) are NOT made of the same patented sponge material as ATI's patented Hydro sponges and thus do not perform nitrification at the same level. These lower end sponge filters also degrade much quicker, as many users can attest to.
A couple of the reasons for better test results when compared to an under gravel filter, is that a well designed sponge filter does not have “dead” spots, nor do sponge filters trap decomposing organic mulm in pockets, such as is the case with under gravel filter plates (which can lower KH/pH, increase nitrates, and even promote Aeromonas or Saprolegnia pathogens!)
In addition, these tests showed that these filters were also superior to most popular power (HOB) filters for bio filtration (such as the Marineland Bio Wheel).
Bio Wheels are touted for their ability to host beneficial nitrifying bacteria and yet, this simple sponge filter outperformed them.
Please see this article for more specific information on Bio Wheels:
Bio Wheels: Do they Work?
*Patented Hydro Sponge Filters
*Aquarium Sponge Filter Kit
*Aquarium, Pond Nitrogen Cycle; Nitrification
*Aquarium Chemistry; Correcting KH/pH
*Saprolegnia; Treatment, Lifecycle in Aquariums
*Sponge filters are a much better choice for bio filtration for planted aquariums over popular canister or HOB filters as they strip less CO2.
Only a fluidized sand bed filter exceeds the sponge filter for aerobic bio filtration without as much CO2 stripping for planted aquariums.
A lack of CO2 is one of the limiting factors in a planted tank so it is a huge advantage to have more available for your plants to utilize for photosynthesis!
*Sponge filters are the clear choice for shrimp aquariums, especially where shrimp are breeding.
The reason is that you can get a much more gentle current, when the filter sponge is mated with an air pump and diffuser.
More importantly, there is no way a baby shrimp can get sucked into the filter as they can with most other filters. The only safer option would be an under gravel filter, but this is a poor choice for other reasons.
*Sponge Filters are probably the best choice for Betta bowls or tanks due to their bio efficiency, lack of turbidity, and low risk of fin damage.
Sponge Filters are also the filter of choice among breeders (including use in their display aquariums), especially high value discus breeders.
In both cases, this is because of the safety they provide to the fish as well as their huge capacity for biological filtration which results in fantastic water quality that is so important for discus as well as other achieving viable fry.
*Even for large aquariums, sponge filters, such as the Hydro Sponge #5 PRO (or even Hydro Pond #2 for even larger aquariums/sm. ponds), often provide superior biological filtration when compared to popular HOB filters such as the Aqua Clear 70.
This is not to say the AC 70 is a bad filter, either. It is not. Nonetheless, my controlled tests showed that sponge filters were capable of much higher biological filtration than even a good filter like the Aqua Clear!.
*Hydro Sponge #5 PRO
*Hydro Pond #2; For Small Patio Pond or Large Aquarium
With some HOB Filters, such as the Penguin Bio Wheel filter, the results of our controlled biological filtration tests were even more dramatically in favor of sponge filters. (For example, I conducted tests with a Penguin 170 vs. a Hydro Sponge #3 in getting these results.)
Finally, although many aquariums keepers are convinced that many wet/dry and canister filters are the "be-all, end-all" for aerobic bio filtration, this is NOT the case. When we used canister filters in our tests, we found otherwise, especially when compared to larger sponge filters such as the Hydro Pond models (which are often used for large aquariums or aquarium wet/dry systems).
When one considers the simplicity of a sponge filter over most canister filters, this is a "no-brainer" for savvy aquarium keepers that find canister filters too cumbersome!
As noted earlier, only a fluidized sand bed filter outperforms a Hydro Sponge Filter for aerobic bio filtration. In fact, some fluidized sand bed filters outperform even the most pricey canister filters such as the Fluval FX5 for aerobic bio filtration!
When you consider cost, simplicity of set up, and maintenance with its capacity for filtration, a sponge filter is clearly something to seriously consider in your aquarium build.
Product Reference: Fluidized Sand Filter; Latest Generation by TMC
*Sponge filters are also available as pre-filters.
Using a sponge pre-filter extends the time between cartridge changes in power (HOB) filters, slows the accumulation of organic debris buildup inside a canister filter, and prevents fish fry from being sucked up the intake tubes of the filters.
More importantly, a sponge pre-filter can add some very essential bio filtration redundancy to often woefully inadequate HOB filters that frequently lose much of their bio capacity with each filter change.
For more about Sponge PreFilters, see this section later in this article:
Sponge Filters as Pre-Filters
*Filter Max Sponge Pre Filters
*Sponge filters do perform mechanical filtration (removal of debris from the water column), however this is not where they excel.
Biological filtration is their strength, which is why the best filtration would be a combination of a sponge filter and a HOB (power filter) such as the more premium Rena Smart or SuperClean Filter or SunSun Value HOB Filters.
These would provide a great combination, a one-two punch!
When a separate sponge filter is employed with an aquarium power filter, canister filter, etc, this improves redundancy of filtration in the case of one filter failing or accidentally being "over-cleaned" (where beneficial bio filtering bacteria are destroyed).
*Rena Smart & SuperClean Filter
*SunSun Value HOB Filters
The only aspect of aquarium/pond filtration where the sponge filter falls short is in chemical filtration.
This can be added with the use of activated charcoal, or other adsorbent. However, even if the sponge filter is the only means of filtration, it should be noted that most established/healthy aquariums do not need constant chemical filtration. This is especially true in the case of planted tanks.
As well, the aquarium keeper could place a nylon bag with Nirox Superior Grade Carbon, SeaChem Purigen, or other chemical filter media at the base of the sponge filter and the movement of water around/through the sponge filter will allow for some chemical filtration.
The picture to the left demonstrates the use of a prescription bottle for a DIY carbon filter. This can be placed under or behind a sponge filter where the water current is stronger. I have found this to be very useful in tanks where the sponge filter is the primary filter in a small aquarium such as a Betta tank.
In this picture API's AmmoCarb is being used.
There are a couple other options for aquarium keepers that can negate the need for chemical filtration. One is the good old fashioned method of simply performing regular water changes. Or, the addition of a power (HOB) filter such as the SunSun HBL-501/701.
Either of these filters would allow you to use chemical filtration and would provide a good compliment to your sponge filter. Even though water changes will likely still be necessary, power (HOB) filters could lengthen the time period between them.
Another more obvious negative reason against the use of sponge filters is a question of pure aesthetics.
While the ATI Sponge Filters are, pound for pound, just about the best aerobic nitrifying bio filters you can buy, many people do not like the looks of them.
Despite the clear benefits to these filters, there is still an ugly sponge in your aquarium. Rather than seeing this as an obstacle, some consider it a creative challenge.
Many aquarium keepers simply use rocks, plants and/or other décor to hide these sponge filters or pre-filters. Or, a black/dark background on your tank can also help the sponge be less noticeable. For many breeders, fish farms, and the like, the negative aesthetic aspect of the sponge filter is easily overridden by their inexpensive high biological filtration capacities.
*Nirox Superior Grade Carbon
*ATI Sponge Filters from AAP
Let's get back to the positive attributes of sponge filters and their applications.
Often, aquarium filter kits that are made up of quality sponge filters along with air pumps or power heads are superior to many of the aquarium kits that are sold in the bigger pet stores.
These are the "starter kits" that come with a small tank and are often very basic aquarium power filters, or even basic corner filters (or similar) with little bio filtration capacity. Beginning aquarists would be better served to consider a simple power head and sponge filter in their first tanks!
This is especially true of big box department store or chain pet store kits that rarely have the bio capacity of a sponge filter kit such as one that utilizes an ATI Hydro Sponge. Simplified maintenance along with superior bio filtration capabilities would equal greater chances of success for beginning fish keepers.
Product Reference: Aquarium Filter Kits, utilizing Premium Sponge Filters
See also this article where "lowly" sponge filters beat out HOB filters with bio wheels:
Aquarium Answers: Do Bio Wheels live up to the hype?
Testimonial to the facts of Sponge Filtration:
"The sponge filtration was inspired by Carl more than 2 years ago when I started into the hobby. Since then, I have progressed to using sponge filtration as the only filtration in my 210 gallon planted freshwater tank. The seeded sponges were used when combining 5 fish tanks into one tank.
Two weeks later, I am enjoying my aquarium.
My fish include a 2 yr old scat fish( was in fresh water at lfs), 8 Bolivian rams( just laid eggs again), 2 German rams( new male in the pair), 5 angels( have laid eggs, no fry), 7 adult dollar fish ( 2 yrs old) and 5 juveniles), a 2yr old dinosaur bischer, 30 cardinals and assorted neon tetras, 1 cory(left), 1 curviceps,4 platys(had fry).
I discarded the canister filter, biowheel filter, and use sponge filtration exclusively. Thank you for diligent,intelligent, and thoughtful sharing of your knowledge."
Jacqueline A., Florida
American Aquarium Products:
Frequently Asked Questions
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Here are some Basics about Aquarium Sponge Filtration:
Sponge filters work by having aquarium water drawn through the porous sponge material in which debris from the water column is trapped mechanically. At this time, aerobic bacteria living in the pores feed on nitrogenous wastes such as ammonia and nitrites that are suspended in the water.
*Stackable Sponge Filter
If you would like more information on sponge material, please see the following article:
Sponge Media Material
FURTHER SPONGE FILTRATION INFORMATION
How a Sponge Filter Works/Functions
Freshwater Aquarium Basics; Filters
The air pump method is generally the better choice for these reasons:
Sponge Filter/Air Pump Combinations Suggestions:
Please note that these suggestions are far from an exhaustive list, so matching similar sponge filters and similar air pumps should yield similar results (although it is noteworthy that there are no equals to the patented Hydro sponge filter, even though most air pumps are quite similar in quality and design).
*Hydro Sponge #1 or #2: SunSun YT-301, Million Air 200, Fusion 300.
*Hydro Sponge #3, #4, or #5: Million Air 200, Fusion 300.
*TWO Sponge Filters: SunSun YT-302, Million Air 300, Fusion 600.
*FOUR to SIX Sponge Filters: Fusion 700, (an air line control kit is suggested for more than 2 per air pump outlet).
*Million Air 200
*Million Air 300
*Air Line Control Kit
*Standard Airline Tubing
When attached to a power head, the pump pulls the water thru the sponge.
With this method I recommend using an air diffuser that generally comes with most power heads to improve dissolved oxygen levels (unless used in a planted freshwater aquarium).
Even if you cannot, or choose not, to use an air diffuser (not all power heads have this feature), you can still aerate the aquarium through breaking the water's “surface tension” using either any directional control that your power head has, or by placing the Power head (pump) outlet near the surface so as to cause ripples on the surface.
With a power head, you will not see any bubbles flowing up the lift tube as with an air pump. However, with both methods there is a rising column of water through this tube that in turn is pulling water through the sponge filter material.
The Hydro Sponge #5 can handle flows up to 400 gph (depending on bio load), if a higher flow is required, the Hydro Pond Filter #2 or #4 can also be used in an aquarium (I have often used the Hydro Pond #4 as a pre-filter for high gph pumps in wet dry sumps).
The Hydro Pond #4 is pump driven and can handle flows up to 1500 gph.
Hydro Pond #2 is air driven and can handle flows up to 1000 gph. And of course the Hydro Pond Filters can be used in ponds where they are excellent complimentary filters or even stand alone filters (usually in low bio load ponds).
*Hydro Pond Filter #4
*Hydro Pond Filters
The power head method is generally the better choice for these reasons:
Please see this short video highlighting the differences between an air pump powered sponge filter or a power-head powered sponge filter:
Aquarium Air Pump vs Water Pump Video
The picture to the left shows a simple suggested large aquarium set up using a Hydro Pond #4 Filter (a Hydro Sponge #5 would work well too) and the differences in flow using either air pump or a power head.
In addition, please note the suggested rock placement you can use to keep the filters from being knocked over if large fish, such as Oscars, are present.
With both air pump or power head methods, the water is pulled through the sponge filter media where debris is mechanically trapped and aerobic bacteria remove nitrogenous waste such as ammonia and nitrites.
For ponds, a more porous sponge media is better to allow a better flow rate and less accumulation of small debris from mechanical filtration that might easily clog a more 'fine to medium' sponge.
For aquariums with internal, pre-filter, or standard sponge filters, a medium porous sponge material with many tiny pores to trap bacteria is best (again this is where the Hydro Sponge Filter excels with its patented design).
*Hydro Pond #4 Filter
*Hydro Sponge Filter
With a new sponge filter, your filter primarily operates mechanically (trapping debris in the sponge which can be rinsed/squeezed out in de-chlorinated water), while the more important bio feature of utilizing nitrifying bacteria to remove toxic ammonia & nitrites takes 4-8 weeks to be fully functional. This can vary due to the age of the aquarium or new tank cycling methods. Please see this excellent article for further information on this subject:
“Aquarium Nitrogen Cycle; Cycling Methods”.
*I should note: from my experience, even though a power head may move more water, I prefer connecting sponge filters to air pumps over water pumps as I find this application to be more simple, less messy, and having less problems with fish knocking power heads off the lift tubes. Your experience may vary but this is what I have found.
When deciding on how high the lift tube should go (whether air driven or pump driven), consider the flow pattern you would like to achieve in your aquarium. I recommend as large a pattern as possible. Therefore, I cut the lift tubes (easily done with a hacksaw) as close to the water surface as will allow for evaporation and other minor changes in tank level and remain submerged.
With some very small tanks (such as Betta tanks), I run these sponge filters on air power and I do not use the clear lift tube at all. Instead, I only attach the air diffuser to the bulls-eye of the sponge filter.
Even when air powered, the air lifts the water through the filter to the top of the lift tube where the water then exits, however, the air bubbles will continue to the surface. The picture to the left (click to enlarge) shows these differences.
For tall/deep aquariums; the use of lift tube extensions can be used to provide a better flow pattern.
The Hydro-Lift can be used with the 1 inch high flow outlets found on the Hydro Sponge Filter. In addition, these lifts work for both air-driven or water-driven applications.
Generally, the use of lift tube extensions can be an advantage for flow patterns, but not always, especially if upper level HOB filters are used. A deep aquarium would be just fine with short lift tube combined with a "hang-on-the-back" power filter providing upper circulation. However if the sponge filters are your primary source of filtration, I would suggest the use of lift tube extensions for deep aquariums.
*Hydro-Lift; Sponge Filter Extension
*Power Head (water pump)
*API SuperClean & Smart "Hang on the Back" Power Filters
Use with Other Filters;
If other filters are present, such as a "hang-on power filter," then, generally your best results will be achieved by placing the sponge filter on one side and the hang-on power filter, or other filter, on the other side (such as the return from a canister filter).
Since hang-on power filters have a water fall effect, these have less horizontal water movement, so in tanks over 36 inches in length the use of a power head on your sponge filter is suggested for better horizontal circulation.
For tanks under 24 inches in length, generally the air pump method will achieve a good circulation pattern.
If power heads or related circulation pumps are already present (such as those on many internal filters too), the use of a air pump driven sponge filter with its superior vertical circulation would generally be most complementary.
If you desire less agitation when using an air pump to power your sponge filter, I recommend cutting the top of the lift tube as close to the surface as possible. I also recommend using an optional air diffuser with your sponge filter which will produce a smaller bubble than a sponge filter used without a diffuser, thus resulting in less agitation of the water.
Please note that air diffusers are sold separately with most brands of Sponge Filters.
If further agitation reduction is desired/required (especially with small fish bowls), the use of air line control valves of valve kits can be used (a valve kit can be used to bleed off excess air pressure).
Air Pump Attachment
*Diagram for sponge filter with an air pump installation (click to enlarge):
This next picture displays a cut away view of a Hydro Pond #2 Filter, showing connection to an air line for use with an air pump.
Outside of this being a double sponge with two bulls eyes instead of one as per standard Hydro Sponge Filters, the internal design is the same for all sponge filters when used with air driven power.
This filter is excellent for both large aquarium use or Patio Pond use (such as container ponds)
Power Head Water Pump Attachment:
These two pictures show sponge filters set up with basic power head pumps such as the newer generation SunSun JP-23 pictured here (similar to many other older generation basic power heads such as the Marineland, Maxi-Jet or AquaClear).
I should also note that, while these diagrams shows a secure fitting for many aquariums from my experience, for large fish (such as adult South American Cichlids), I would suggest using heavy rocks to brace the sponge filter & power head as these fish will often knock the power head off the lift tube.
Please Click on the pictures to enlarge for a better view
*Hydro Sponge #5
*Hydro Pond #2
*SunSun JP-23; New Generation Aquarium Power Head
*Marineland Power Head Pump Review
*Maxi-Jet Power Head Review
*Hagen AquaClear Power Head Pump Review
Additional Sponge Filters for Small Aquarium, Bowl Applications
The picture to the left displays how to utilize a Hydro Sponge #2 to make a Mini Hydro Sponge for use in small bowls (such as 1 quart, 1 liter) or small 1-2 gallon aquariums where the Hydro Sponge 1 is not desired.
The beauty of this idea is that, not only do you get a nice compact Sponge Filter, but you get a spare sponge too at no extra cost!
Additional Sponge Filters for Breeding or Large Aquarium Applications
As already noted earlier, Hydro Sponge Stackables can be used to add additional filtration in breeding tanks and also to provide safe areas to hide for fish babies (fry).
The use of these sponges, especially the Hydro Sponge 5 Stackable also allows for expansion with larger tanks, often with surpassed bio efficiency and ease of maintenance over frequently over-touted canister or wet-dry filters.
As well, when a #5 stackable is added to a #5 PRO filter, this will provide different levels of mechanical filtration (as well as flow rates), which further increases the viability of the sponge filters to be the primary aquarium filter.
Please click on the picture to the left for an example.
*Hydro Sponge #2
*Hydro Sponge 5 Stackable
*#5 PRO filter
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Here is a basic sponge filter installation video:
SPONGE FILTER TROUBLESHOOTING
UV STERILIZER SPONGE FILTER APPLICATIONS
*ReSun King 1A Pump
*Hydro Sponge #3 Filter
*SunSun JP-23 Power Head
*Rio 1700 Pump
*Terminator 7 Watt UV
*TMC 8, 15, & 25 Watt Vecton UV Sterilizer
*SunSun CUP Series UV/Filter
SPONGE FILTERS AS PRE-FILTERS:
Besides the more common stand alone sponge filter, the sponge pre-filter is also a viable sponge filtration option. These are especially useful in preserving viable nitrifying bacterial colonies in HOB filters during changes of filter media, especially with cartridge filters that don't have other means of maintaining bacteria., as many of these filters lack bio media chambers
OTHER SPONGE FILTER USES
Another use of Sponge Filters is as a basic Pond Filter or using a Hydro Pond Sponge Filter as an excellent and efficient large flow pre-filters in aquarium sumps for both salt and freshwater aquarium systems.
See the picture to the left as an example which also includes a Filter Max over the intake to the sump.
These same Hydro Spond Filter that are designed for small pond use also make excellent high capacity bio filters for large aquariums.
Whether it be the double reticulated air driven #2 Hydro Pond or the water driven #3 (single) or #4 (double), these high capacity sponge filter can be the PRIMARY filters for aquariums as large as 250 or even larger in multiples or as the secondary filter!
Pictured are a water driven #3 to the left and an air driven #2 to the right
Product Resource: Hydro Pond Filters For Large Aquariums, Sumps
Many, if not most, internal/submersible filters are essentially sponge filters that are self-powered sponge filters.
These have the advantage of being easy to tuck up high in an aquarium corner more out of the way than a standard sponge filter.
Also, with the SunSun HJ-752 Filter pictured here you can cut the sponge in half to allow more room, and then add other filter media such as carbon or Matrix. However, a small bag, or other means of blocking the carbon from being ingested into the motor, should be used.
Some of these filters also have multiple chambers where other filter media can be placed (example the SunSun HJ-952 (210 gph)).
The disadvantage, especially when compared to the patented Hydro Sponge filter line is their sponge bio capacity is much lower based on the size and efficiency of the sponge material.
The sponges (foam inserts) found in filters such as the Aqua Clear Filter also qualify as a sponge too. But they are not sponge filters in the classic sense.
These “foam inserts” do NOT have nearly the same pore capacity as comparably sized Hydro Sponge Filters. Care and use should be considered the same for this type of sponge inserts.
One little “trick” I like to do with these sponge inserts is to cut them in half or even thirds so as to “seed” multiple sponges for use in helping jump start the nitrogen cycle in other tanks or as back ups to other tanks under treatment.
*SunSun HJ-752 Internal/Submersible Filters
*SunSun HJ-952 (210 gph)
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PROPER SPONGE MEDIA CARE:
The main problem with sponge filter media of any type is clogging due to mechanical filtration.
SPONGE FILTER SUMMARY/ATTRIBUTES:
Sponge filters can even be used in ponds.
With the Hydro Pond Filter, simply attach a power head pump (such as a Rio 1700 or Rio HF), then run your return line wherever you like (waterfall, etc.), or the Hydro Pond II can be run off a simple air pump. These filters can work on ponds up to 1500 gallons (or more with additional units).
These Hydro Pond Filters (the #4 in particular) also work well in large aquariums or in the sumps of large filtration systems, especially when you need flows in excess of 400 gph.
*Hydro Sponge #5 PRO
*Hydro Pond Filter IV
*"Hydro Pond Filter"
*Do Bio Wheels work as claimed
*Aquarium Filtration; Fluidized Sand Filter
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Here are a Few Myths:
Hydro Sponge Review from Renee (goldenpuon) from “Everything Aquatic”
"I thought I'd write a review of the Hydro Sponge filters I purchased from Carl a while back. The results are excellent too. Better than any sponge filter I've ever owned. It picks up fish waste very well and now I have to do less than half the cleaning for my tank. I had a guppy tank I was cleaning every two days with a micro filter installed. Now all I have to do is clean it every 1 1/2 weeks!
The Hydro Sponge also creates a good amount of water disturbance with very few bubbles produced making it a great for providing oxygen for fish. Its quality is just as good, if not better than most power filters out there. It is also small and doesn't take up much space while providing a great place for beneficial bacteria to grow. This makes it much more useful than really any other filter for tanks with high ammonia, nitrites, and nitrates. It is also much less expensive than filters that require carbon.
All you have to do is replace the sponge every 6 months and it costs little more than a dollar while carbons in power filter must be changed at least every month each costs a few dollars. One of the best filters I've ever owned, I highly recommend it for aquariums of all sizes!
Hope you guys like my review. I'm not just pointing out the positives here, they really are true."
For more aquarium information and articles (pond too), please visit this site:
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