Advantages of the TRUVU Acrylic Aquarium

over a Glass Aquarium

When it comes to comparisons between a TRUVU acrylic aquarium and a glass aquarium it isn't an apples and apples comparison. Consider these facts and decide.


    Acrylic is about 10% clearer than glass.

    Unlike glass aquariums many acrylic aquariums have rounded corners to give the aquarist an unobstructed view.

    Acrylic seams are fused together and last for the life of the aquarium compared to silicone sealant used to seal glass aquariums that can dry out over time and cause leakage.

    Acrylic has more insulating capacity. In a test conducted over 18 months by FAMA magazine* heaters in glass aquariums required 25% more on time than heaters in TRUVU Acrylic aquariums; important in today's energy and cost conscience environment.

    Glass aquariums are twice as heavy as a TRUVU aquarium and are prone to pressure cracking if the aquarium is not level or if it is impacted.

    Drilling glass is extremely difficult, impossible if the glass is tempered. TRUVU acrylic aquariums can be drilled to suit the needs of the aquarist.

    A TRUVU Acrylic aquarium is 17 times more impact resistant than glass; it can take a blow that would destroy a glass aquarium, important if you plan to set up it up in a kid's room. Aquarium maintenance companies routinely choose an acrylic aquarium in commercial settings like, restaurants, bars, doctor's and dentist's offices where safety counts and failure means a legal headache!


Acrylic scratches,  glass scratches too! If you are unlucky enough to pick up a piece of gravel under an algae magnet it can scratch a glass aquarium. The bad news: glass scratches can't be removed, the good news: acrylic scratches can be removed!

Acrylic bows. In the industry, it is called deflection and it is a positive attribute. The rigidity of a glass aquarium is the reason they fail, acrylic deflects like the wing of an airplane it gives slightly to deflect the water pressure.

Thicker material

Our aquariums are built to the industry standards of safety and serviceability that have been in place for nearly forty years. If you wish to have a standard size, or custom size, aquarium constructed with thicker material, TRUVU will be happy to give you a custom quotation.
We realize that some people are concerned with the smallest amount of deflection (bowing). This can be virtually eliminated by the use of thicker gauged acrylic. Please be advised that the cost will increase proportionally.

Acrylic yellows. This claim is a complete falsehood based on the use of styrene based un-polymerized cell cast acrylic nearly 50 years ago! ACRYLIC DOES NOT YELLOW. Cell cast acrylic has been tested in the direct sunlight of the Arizona desert for five years without any signs of discoloration.



*Dewey,Don..  Product Test Aqua Plex TRUVU Aquariums,
  FAMA Vol. 4 No.5, Sierra Madre, CA, 1981

Choosing the Correct Filter and Pump

When choosing a filter the aquarist must select a filter based on the gallon capacity of their aquarium.
To find an aquariums capacity simply multiply the length times width times height and divide by 231. The result will give you the gallon capacity. For example a 48x13x20 aquarium is 54 gallons. When volume is established you can select a filter, refugium or sump to suit your needs.
At his time the aquarist must also decide whether his or her aquarium will be for freshwater or saltwater use. Next the aquarist must decide if it is to be for freshwater fish, saltwater fish or perhaps a reef aquarium housing invertebrates and live rock.
Our Platinum Series offers a complete line of filters; refugiums and sumps that are capable of handling aquaria from 20 to 300 gallons.
The model number designates the maximum size aquarium the filter is designed to handle. For instance a model 75 PSSW salt water wet/ dry filter will comfortably handle the filtration of aquariums from 20 to 75 gallons. Other model sizes include the 180 and 300 models.
All of the Platinum Series filters and sumps are fitted with a single or dual 200 micron bag pre-filter capable of trapping particulate matter as small as .007874”. The micron bag removes ultra fine particulate matter that manages to pass through the DLS pre-filter in the aquarium overflow.

Wet/Dry Filters

The Platinum Series PSSW (saltwater) and PSFW (freshwater) wet/dry filters are best suited to fish only (FO) aquariums. They are capable of handling heavy bio loads (many fish). The PSSW (saltwater) and PSFW (freshwater) filters are available in models 75, 180 and 300.
Both freshwater and saltwater models include a single or dual 200 micron bag pre-filter (depending on size), drip tray and large bio chamber (plastic bio media included). The PSSW, filter has a 10"x10" chamber for an after market Protein skimmer.


The first chamber of PSRF refugium contains a 200 micron bag, the plus model features a 10"x10" area for an after market protein skimmer. The middle chamber provides an undisturbed refuge for live sand, live rock and caulerpa . The third chamber is the return chamber where the pump conveys water back to the aquarium. PSRF refugiums are available in 75, 180 and 300 models.


The PSS sump is a vessel capable of holding an extra volume of water. The sump can be used to house calcium reactors and various live and inert filter media for additional filtration. The sump is also used for kalwasser and calcium dosing. It also serves as protection from aquarium overflow (in the event of power outage) and provides water to keep the aquarium topped off as evaporation occurs. The PSS sump is available in models 75, 180 and 300.



In recent years the conventional wisdom, in aquarium keeping, especially marine fish and reef keeping, has tended toward higher flow rates. Most reliable sources feel that the water volume of the aquarium should be turned 2-4 times per hour for freshwater aquariums and 6 to 10 times per hour for saltwater and reef aquaria. Therefore it follows that if you have an aquarium of approximately 60 gallons and you want to turn that volume 6 to 10 times per hour you will need a pump that is rated at 600 to 1000 gallons per hour.
It is also important to remember that you must take into account the aquarium height. Most pumps are rated at Zero Head. This means they will deliver 600 GPH to 1000 GPH out of the pump; that number is meaningless to the aquarist!
Since the filter is housed under the aquarium, in the stand, it means that the water will have to be piped the height of the stand plus the height of the aquarium. Since most stands are 30” tall and the 60 gallon aquarium, used as an example, is 18” high the pump will have to deliver 600 -1000 GPH @ 48”.Be sure to read the pump manufacturers fact sheet before purchasing a pump to be sure that it delivers the desired flow at the proper height.

Note:We realize that some internet sites recommend turning the volume of water in the aquarium 20-40 times per hour! Based on the experience our company has gained in the past thirty seven years as successful designers of aquarium filters, we feel that this recommendation is overreaching in the extreme.


TRUVU Aquasystem

The original design for the TRUVU Aquasystem was conceived in 1989! The initial design incorporating a built in wet/dry filter was carefully calibrated, flow tested and evaluated with various types and quantities of bio media to achieve saturation levels of dissolved oxygen in carefully monitored testing. After nineteen years the revolutionary original design has stood the test of time and remains virtually unchanged.


Overview: The Aquasystem is a quiet, self contained unit that discourages, salt creep, evaporation and contamination from air borne pollutants. All of the mechanical assets are concealed behind a formed opaque acrylic housing that is permanently attached to the back of the aquarium. The Aquasystem offers an uncluttered viewing area, free of airlines, heaters and siphon tubes.


Filtration methodology: Surface water is skimmed and enters through a notched gate on the left side of the filter (on larger Aquasystems, through a notched gate on both sides of the filter) into the accessory chamber, designed to hold optional features, such as a protein skimmer and heater. The water is conveyed through an aperture in the skimmer chamber into a multi perforated drip tray that holds a fibrous pre-filter that traps detritus. The cleansed water moves through the calibrated holes in the drip tray and rains down onto the DLS* rolls, in the dry section of the wet/dry filter, then moves into the wet section of the filter as it moves through the plastic bio media. The water is pulled into the final chamber by the powerful action of the submersible pump that carries the sparkling clear, oxygenated water back into the aquarium. The TRUVU Aquasystem is capable of quietly moving hundreds of gallons of water per hour.  


*The 4" diameter rolls of DLS found in the Aquasystem are highly effective biological filters. The DLS (Double Layer Spiral) material interleaved with a fibrous material effectively separates the layers allowing the water from the aquarium to rain down through the DLS rolls where beneficial aerobic bacteria oxidize ammonia.



Q. What does the back of the aquarium look like with an Aquasystem installed?

A. Because the Aquasystem is constructed with material that is the same color as the back of the aquarium it is virtually invisible when the aquarium is filled with water.

Q. In what order are the three filtration compartments?

A. Surface water, containing the majority of pollutants, is skimmed and enters through a notched gate on the left side of the filter, facing the aquarium into the first accessory chamber, designed to hold optional features, such as a protein skimmer and heater. The water passes over a spillway onto a perforated drip tray, in the second chamber, that holds a pre-filter that traps heavy waste and oils that accumulate on the water at the surface of the aquarium. The water passes through the drip tray and rains down onto the DLS* rolls, in the dry section of the wet/dry filter, then moves into the wet section of the filter as it moves past the plastic bio media. The water is pulled into the third and final chamber by the powerful action of the submersible pump that moves hundreds of gallons of clean, oxygenated water back into the aquarium water back into the aquarium.

Q. Is the bio pad easy to remove and replace?

A. It couldn't be easier. 1. Remove the Aquasystem cover. 2. Unplug the pump. 3. Lift the drip tray and remove the Bio Pad. 4. Place a receptacle under the pad to keep water off the floor. 5. Rinse the pad off in the sink until it is clean and replace in the drip tray on the grid, replace the drip tray and restart your pump. The pad can be reused several times before discarding and replacing with a new pad.

Q. How often do I need to replace the Bio Pads?

A. As mentioned in the previous question the Bio Pad can be rinsed and replaced to minimize frequent replacements. On average a Bio Pad can be used for about two months before replacing the Bio Pad.

Q. What is the size of the Aquasystem and how many gallons of water will I lose?

A. The size of the Aquasystem depends on the size of the aquarium so it is impossible to come up with a standard size rule. A 55L Aquasystem displaces about four gallons of water about a gallon more than a 6"x6" overflow.

Q. What are the compartment sizes?

A. The first compartment is slightly less than one quarter of the total length of the Aquasystem. The second compartment, where the actual wet/dry filtering takes place, comprises one half of the Aquasystem and the third compartment takes up slightly more than one quarter of the Aquasystem.


Canister filter

The canister filter has been around for many years and it works well as a mechanical filter because of its ability to remove fish waste, uneaten food and free floating algae. A canister filter pulls oxygenated water from the aquarium into the canister where it passes through a sponge pre – filter, filter wool mat and finally various types of filter media like bio – balls or ceramic noodles and is returned to the aquarium via a hose attached to a pump.

In the 1970’s discussion of the “Nitrogen Cycle” pointed to the vital importance of an oxygen enriched, undisturbed, filter bed where beneficial bacteria ( nitrosomonas and nitrobacters) could convert toxic ammonia and nitrite into relatively harmless nitrate. It demonstrated that detritus removal alone was not the key to successful aquarium management.

The concept of siphon tubes pulling detritus from the bottom of the aquarium was questioned by Peter Wilkens in his book, “The Saltwater Aquarium for Tropical Marine Invertebrates”. Mr. Wilkens (the father of the “Berlin Method” of filtration) felt that sucking water from the bottom of the aquarium was “nonsense” he stated that the water at the surface of the aquarium, just thousandths of an inch thick, contain the majority of the organics we wish to remove.

 In a book entitled, “Aquarium Hygiene”, Dr. Hellmuth Wachtel pointed to the reason that the canister filter performs inadequately when he said: “It works submerged”. He went on to say “water leaving the filter is practically devoid of oxygen”. Kaspar Horst and Horst Kipper in their book, “The Optimum Aquarium”, restated Dr. Wachtel’s hypothesis when they referred to the canister type filter as an “oxygen trap”.

Another drawback of the canister filter is maintenance. The filter is much more difficult and messy to service than a Wet/Dry filter and as a result the aquarist puts off cleaning the filter until it is clogged and is running slowly. Over time the “O” ring that keeps the top of the canister from leaking can become worn or torn causing a failure resulting in a small flood!

In the event of a power outage the aerobic bacteria, dependant on a constant supply of oxygen rich water start dying immediately, replaced by anaerobic bacteria. When power comes back on fouled, oxygen depleted water, is pumped into the aquarium!


                             Literature Cited
Wachtel, H. Aquarium Hygiene, D. Van Nostrand Co., 1966, 31-32
Horst, K, Kipper, H, The optimum aquarium, AD aquadocumenta Verslag GMBH, 97
Wilkens, P., The Saltwater Aquarium for Tropical Marine Invertebrates, Engelbert Pfriem, 197, 32


The Under Gravel Filter

The under gravel filter was really the first filter that provided a healthy aquatic environment for freshwater and saltwater fish. The U.G. filter was “the” filter for serious aquarist from the 1970’s until the emergence of the wet/ dry filter in the 1980’s.

The operating principle of the U.G. filter was simple and straight forward; the entire bottom of the aquarium was covered with raised slotted plastic plates with lift tubes fitted into the plastic grids, in the rear corners of the aquarium. The U.G. grids were then covered with several inches of uniform sized gravel that became the filter media.

Airlines fitted with ceramic or wooden air stones were placed inside the lift tubes near the bottom of the tube. When the air, supplied by a small air pump, was introduced bubbles rose in the lift tubes raising the water up the lift tube, exiting into the aquarium.

The U.G. filter didn’t have any moving parts, didn’t require changes of filter media and operated by the use of a simple air pump, but the U.G. filter did have limitations.

        * The gravel bed must be uniform. Hills and valleys will cause uneven flow. This makes for a rather boring aquascape.
        * Areas covered by rocks and decorations prevent water to flow through the U.G. plates.
        * The water being air lifted is pulled from an area closest to the lift tube causing uneven filtration and dead spots in the gravel toward the center of the filter.
        * The U.G. filter does not work well with aquarium inhabitants that are diggers like Cichlids, Triggers and Parrot fish.
        * Over time organic debris can clog a U.G. filter causing a dangerous buildup of anaerobic bacteria causing the production of hydrogen sulfide (“rotten egg” odor) and methane.
        *  The most obvious limitation of a U.G. filter lies in the fact that it works submerged; like the canister filter a power outage renders the filter inoperative and potentially deadly. Aerobic bacteria start to die off without a supply of oxygen enriched water and deadly anaerobic bacteria take over.

To recap They do a fine job in a small aquarium with small decorative fish that will not disturb the substrate.
 If gravel is arranged in hills and valleys (as it usually is) oxygen rich water will seek the lowest points in the gravel and only small patches of the gravel will be rich in nitrifying bacteria. Bottom vacuuming and fish can rearrange gravel disturbing or destroying colonies of aerobic bacteria.

                             Literature Cited
King,J.M.,Kelley,W.E,Saltwater Aquariums:Principle and Practice,Aquarium Systems Inc.,1973,7
Loiselle,P.V.,The Cichlid Aquarium,Tetra Press,1985,57
Spotte,S.H.,Fish and Invertebrate Culture Water Management in Closed Systems,John Wiley and Sons,1970,9-13
Wachtel, H. Aquarium Hygiene, D. Van Nostrand Co., 1966, 30


The Refugium


In the early 1960s an Indonesian entrepreneur named Lee Chin Eng introduced the world to a revolutionary concept in saltwater aquarium keeping called “Natures System”. His revolutionary method; no mechanical or chemical filtration!

The method Lee Chin Eng devised was basically an aquarium loaded with live rock. Lighting was supplied by sunlight, he didn’t make water changes and the only compromise to a totally natural system was the use of an air pump with a length of tubing that gently bubbled under the “live rock” in the rear of the aquarium. This basic concept was the forerunner of the refugium.

The function of a refugium, as the Latin name implies, is a “refuge” for minute living animals. A refugium can be quite small and compact, some hang on the back of an aquarium like an outside power filter. Usually they are located under the stand like the TRUVU PSRF series. As a general rule the refugium should be approximately 20% as large as the aquarium.

The operation of the refugium is quite simple. Water exits the aquarium and enters the first chamber, where the water is pre-filtered through a 200 micron sock to capture detritus. There is room in the first chamber of the TRUVU PSRF PLUS series refugium, for a protein skimmer should the aquarist choose to use one. The nutrient rich water then passes through a slotted divider into the main chamber of the refugium. This is where, “live sand”, “live rock” and macro algae like chaetomorpha chaeto and caulerpa spp chemosynthetically neutralizes toxic nitrites (NO 2) and nitrates (NO 3). The water flows through a second slotted divider into the third chamber where a pump conveys the water back into the aquarium.



                             Literature Cited
Straughan,R.P.L.,Anenome Rocks, Saltwater Magazine, Jan./Feb. 1966
Wilkens, P., The Saltwater Aquarium for Tropical Marine Invertebrates, Engelbert Pfriem, 17


Wet/Dry filters

In 1986 a gentleman named George Smit submitted a seven part series of articles to Freshwater and Marine Aquarium magazine. Publisher editor, Don Dewey published the articles between January and July of that year and the rest, as they say, is history!

The Wet/Dry or Trickle filter as many people prefer to call them, revolutionized aquarium keeping.

 As mentioned in previous articles on this site, the Under Gravel and Canister filter have serious drawbacks. For a discussion of those drawbacks please visit the Under Gravel and Canister filter articles.


Aquarium water is pre-filtered through a roll of DLS, located in a skimmer box or overflow chamber The water skimmed from the very top layers of water traps oils, lipids, detritus and waste. The water travels down the skimmer chamber and enters a flexible hose that conveys the water into the W/D filter where it falls onto a uniformly perforated drip tray that rests above the filter media. The water rains down over plastic bio spheres in a micro thin film causing carbon dioxide to be expelled, replaced by atmospheric oxygen drawn through the vented lid of the filter . Over time the interstices of the plastic spheres become a home for to billions of beneficial, denitrifying, aerobic bacteria.
Approximately 2/3 of the plastic bio media in the filter chamber remains above the water level of the filter this is referred to as the DRY portion of the filter. The term DRY is a misnomer, Damp would be more descriptive. The remaining WET portion is the attachment point for additional nitrifying bacteria on the submerged bio media.
The water then moves through into the pump chamber where it is pumped back into the aquarium. Many aquarists place a protein skimmer in the pump chamber for additional filtering capacity.
There isn’t any filter that can deliver higher saturation levels of dissolved oxygen than the Wet/ Dry filter.
 Because a full 2/3 of the W/D filter bio media is above water, a power outage has little effect on the aerobic bacteria. A power outage would have to last for nearly 24 hours before the aerobic bacteria started dying.
Reef keepers may choose to use a TRUVU PSRF Plus refugium and protein skimmer rather than a Wet/Dry filter. Invertebrates don’t tolerate Nitrate (NO3) at levels over>10ppm. Nitrate (NO3) levels in a well managed Wet/Dry filtered aquarium range from >10-15 ppm. Fish can tolerate Nitrate (NO3) levels of >30 ppm.

Literature Cited                            
Blok,J. Biological Filtration For the Marine Aquarium Pt. III, FAMA Vol. 9 No.11 1986, 64-66
King,J.M.,Kelley,W.E,Saltwater Aquariums:Principle and Practice,Aquarium Systems Inc.,1973,8
Montgomery,W. The Wet Dry Filter, FAMA Vol. 13 No 1,1990, 110,112,114,118,154
Smit,G., Marine Aquariums Pt. I, FAMA, Vol. 1 No. 9 1986, 35-37,39-42, 84,85
Smit,G., The Ecological Marine Aquariums Pt. III, FAMA, Vol. 10 No. 7, 1987, 32-36



Acrylic Aquarium / Filtration Care


By following these guidelines your TRUVU acrylic aquarium/filter will retain its' beauty for many years.

With proper care your TRUVU acrylic aquarium/filter will provide you with years of trouble free service. Since acrylic is 10 to 17 times more shatter resistant than glass it is much safer. A blow that will shatter a glass aquarium will just scratch an acrylic one. A scratch can be easily removed with an acrylic safe scratch removal kit.


Your TRUVU aquarium/filter should be given the same care and treatment as any fine furniture. Many cleaning preparations commonly used in the home are not suited for use on acrylic.

Please DO NOT USE: Scouring powder, Strong solvents, Bleach, Lysol sprays, Windex or similar products. Nor Benzene, gasoline, acetone, carbon tetrachloride or denatured alcohol. Also cloths of rough texture or sponges with rough surfaces. Be sure cloth or sponge is free of grit or aquarium gravel that will scratch the acrylic surface.

Please DO USE: Brillianize spray cleaner and polish for cleaning the exterior of your TRUVU acrylic aquarium. An acrylic safe scratch removal kit for the removal of small scuffs or scratches. On the interior use only acrylic approved aquarium cleaning pads.

Proper stand selection: Acrylic aquariums require a "solid support top" stand. Use of an "open" top stand is not advised and is not covered in the warranty. In the event you can not locate a solid support top stand use of plywood or equivalent will suffice.


Metal Halide lighting: With the popularity of "Reef" aquariums many different types of lighting have been introduced over the last few years. One such type of lighting is Metal Halide. Although most types of Metal Halide lights are safe for use it is not recommended to use Metal Halide lights that produce light in the wavelengths below 400 nanometers. Light below 400 nanometers has been proven in tests** to be destructive to organic material. Since acrylic and all plastics are organic materials this applies to aquariums as well. Any damage to your TRUVU acrylic aquarium from use with Metal Halide lighting is not covered in the warranty. Please select a Metal Halide light that produces light above 400 nanometers or consider the very popular "Compact Fluorescent" , T5 or LED lighting.

Filter Media

Bio Ball Filter Media

One inch inert plastic bio balls have been a popular method for off gassing and aerobic bacterial attachment sites in wet/dry filters for nearly two decades. The unique plastic balls are designed with superior “wetting” characteristics that keep the balls moist for long periods of time; creating a perfect attachment point for billions of beneficial nitrifying bacteria. The initial cost of the bio balls is offset by their durability; they can be used and re-used for many years of service.

Tip: Many aquarists “seed” a wet/dry filter or refugium in a newly set up aquarium with a portion of the bio balls from an established aquarium to reduce the negative effects of elevated ammonia (NH4) levels.

200 Micron filter bag
Application: Wet/Dry, Refugiums & Sump Pre-Filter

The 200 micron filter bag measuring 4” in diameter by 14” in length finishes the cleanup job initiated by the DLS (Double Layer Spiral) aquarium pre-filter. The micron bag acts as a water polisher, trapping minute particulate matter as small as .007874 from entering the wet/dry, refugium or sump.
The 200 micron filter is also sold individually as a replacement item.

DLS Combo-Pack
2-4 Rolls of DLS and Pre-Filter Pads

The DLS combo-pack is a replacement filter pack for Aquasystems™ and hanging wet/dry filters. The package contains 2-4 rolls of DLS (depending on aquarium size) and 3 micro fine polyester pre-filter pads.
The filter pad acts as a mechanical filter; simply place the polyester  pad under the drip tray, on top of the grid material, over time it will collect detritus, skimmed from the top layers of aquarium water. Change the pre-filter pad when it becomes soiled and matted.
The DLS rolls should be replaced, singularly, to avoid the depletion of beneficial aerobic bacteria and interruption of the biological process.

Tip: Remove the first DLS roll and replace with a fresh roll. NEVER replace more than one DLS roll at a time to prevent catastrophic loss of the nitrifying bacteria!





Aquasystem™ DLS Filter

The 4” diameter rolls of DLS found in the Aquasystem and Mighty Max filters act as highly effective biological filters.
The DLS (Double Layer Spiral) material interleaved with a micro fine polyester material effectively separates the layers allowing the water from the aquarium to slowly rain down through the DLS rolls where beneficial aerobic bacteria attach themselves to the interstices oxidizing ammonia and nitrites.

Polyester Pre-Filter Pads

A handy 3 pack of DLS micro fine polyester pre-filter pads designed for the TRUVU Aquasystem and hang on back wet/dry filters. The polyester pre-filter pad acts as a mechanical filter ensuring that the Bio Balls or DLS (Double Layer Spiral) rolls, in the wet/dry filter, remain free of detritus buildup that obstruct and impede the effectiveness of the biological filter.
Change soiled filter pads when they break down and become too open and porous to pre-filter detritus.

Tip: Rinse off pad every week to wash away detritus. It will prolong the pads mechanical filtering capacity.


DLS Pre-Filter with stand pipe
Application: Internal and External Overflow

The DLS (Double Layer Spiral) pre-filter with stand pipe is a mechanical filter, not a
Biological filter. The stand pipe fits into the 1” bulkhead fitting in the pre-filter chamber of the over flow. It is available in 6” – 12” – 16” and 22” lengths to fit various size aquariums.
The 5” diameter roll of DLS material is interleaved with a micro fine polyester material that effectively traps detritus to ensure a clean flow of water as it enters the Wet/Dry, Refugium or Sump.

Replace the pre-filter when noticeable impedance in the flow causes pump cavitation.
The pre-filter will provide many months of protection. Service functionality depends on bio load and feeding regimen.

Product Information Brochures
( .pdf format)
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Protein Skimmers
Freshwater Aquariums
Aquarium Filtration
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