What’s the difference between Fluval G3 and G6 Filters?

If you are looking for a high-tech filter for your fish tank, then you will most likely run into the Fluval G Series during your research. So, which of the two models, the G3 and G6, are best suited for your fish tank?

You can find out in our comparison guide at Aquarium Blueprints below.

Quick Summary

Overall, the G Series is a great high-tech canister filter for those who are into the more advance aspects (such as TDS and chemical filtration) in fish keeping.

The G6 provides a better flow rate and can handle more filtration media. If you want a lot of flow and/or have a fish tank of at least 80 gallons, then you should get the G6.

With that said, the G3 is perfect capable of handling fish tanks of 80 gallons or less as it still provides a pretty good flow. Just make sure you don’t severely overstock your fish tank with a lot of fish.

Fluval G3 vs. G6 Comparison Chart

Aquarium Capacity

The Fluval G3 Advanced Filtration System has been rated for fish tanks at up to 80 gallons (or 300 liters). The Fluval G6 Advanced Filtration System has been rated for aquariums that are twice as large at up to 160 gallons (or 600 liters).

Pump Outputs

When it comes to pump output capabilities, the G6 can output 82 percent more than the G3 at 120V/60Hz. The G6 also outperforms the G3 at outputting 91 percent more water volume at 230-240V/50Hz. You can check out the full stats below:

• G3 at 120V/60Hz: 365 gallons per hour (or 1,380 liters per hour)
• G6 at 120V/60Hz: 665 gallons per hour (or 2,510 liters per hour)
• G3 at 240V/50Hz: 340 gallons per hour (or 1,285 liters per hour)
• G6 at 240V/50Hz: 650 gallons per hour (or 2,460 liters per hour)

Filter Circulation

Furthermore, the G6 Filter outperforms the G3 Filter when it comes from filter circulation. The G6 can move 265 gallons per hour (or 1,00 liters per hour) from within the canister, which is around a little over 43 percent better than the G3, which is capable of 185 gallons per hour (or 700 liters per hour).

Mechanical Area (Foam)

The Fluval G6 Canister Filter also has more mechanical area at 386 squared inches (or 980 squared cm) when compared to the Fluval G3 Canister Filter’s 204 squared inches (or 520 squared cm). Overall, there is a little over 89 percent more area in the G6 when compared to the G3.

Biological Volume

When it comes to biological volume, the G6 Advanced Canister Filtration System (at 1.05 gallons or 4 liters) can hold 75 percent more than the G3 Advanced Canister Filtration System (at 0.6 gallons or 2.36 liters).

Filtration Volume

The G6 also has the advantage when it comes to filtration volume with 74 percent more capacity when compared to the G3. You can find the specifications below:

• G3: 1.32 gallons (or 5 liters)
• G6: 2.3 gallons (or 8.7 liters)

Head Height

The G6 Advanced Filter also has around 20 percent more head height at 50Hz and 23 percent more at 60Hz when compared to the G3 Advanced Filter. You can find the full specs below:

• G3 (50Hz): 5.1 feet (or 1.8 meters)
• G6 (50Hz): 6.1 feet (or 2.1 meters)
• G3 (60Hz): 6.2 feet (or 1.9 meters)
• G6 (60Hz): 7.6 feet (or 2.3 meters)

Wattage

The G3 Canister Filter uses 33 percent less wattage at 120V/60Hz and a little over 39 percent less wattage at 230-240V/50Hz when compared to the G6 Canister Filter. You can find the power stats below.

• G3 (120V/60Hz): 18 W
• G6 (120V/60Hz): 27 W
• G3 (230-240V/50Hz): 17 W
• G6 (230-240V/50Hz): 28 W

Dimensions

Although the length and width are the same, the G6 Advanced Canister Filtration System is 32 percent taller versus the G3 Advanced Canister Filtration System. You can check out the dimensions below.

• G3: 9.8 inches in length x 9.8 inches in width x 9.72 inches in height (or 24.9 cm x 24.9 cm x 24.7 cm)
• G6: 9.8 inches in length x 9.8 inches in width x 12.83 inches in height (or 24.9 cm x 24.9 cm x 32.6 cm)

HydroTech Performance Monitor

What separates the Fluval G Series from other filters is the HydroTech Performance Monitor. Both the G3 and G6 comes with a LCD that displays the maintenance scheduler, electrical conductivity, temperature and flow rate. The canister filters are powered by a microchip flash microcontroller with NanoWatt XLP technology to sense and continually monitor all four aspects. Below, you can see why each indicator is important to the health of your fish tank.

Maintenance Scheduler

The maintenance scheduler basically tells you the cleaning intervals between the biological, chemical and mechanical filtration. The LCD uses the “Days” interval for chemical and mechanical filtrations and the “Weeks” interval for biological filtration.

The scheduler is especially helpful for chemical filtration as the media, such as carbon, will lose its effectiveness over time and will need to be replaced if you need to remove more unwanted chemicals from your tank water. It is also important for mechanic filtration if you want to keep your aquarium looking clean and maintain a constant water flow.

Electrical Conductivity

Electrical conductivity measures how much your fish tank water can carry an electrical current. This is used as a measurement for the total dissolve solids or salts (TDS for short) in your aquarium. Different fish species prefer different TDS. You can find Fulval’s recommended relative conductivity range for the most common species you find in the aquarium hobby below.

20-50 μS/cm:

• Green Neon tetra (Paracheirodon Simulans)
• Red Discus (Symphysodon Discus)

50-100 μS/cm:

• Cardinal Tetra (Paracheirodon Axelrodi)
• Clown Loach (Chromobotia Macracanthus)
• Dwarf Gourami (Colisa Lalia)
• False Rummynose Tetra (Petitella Georgiae)
• German Blue Ram, Blue Ram (Microgeophagus Ramirezi)
• Harlequin Rasbora, Red Rasbora (Trigonostigma Heteromorpha)
• Julii Cory (Corydoras Julii)
• Otocinclus Loach (Otocinclus)
• Pearl Gourami (Trichogaster Leeri)
• Tiger Barb (Puntius Tetrazona)

100-200 μS/cm:

• Angelfish (Pterophyllum Scalare)
• Bronze Cory (Corydoras Aeneus)
• Chinese Algae Eater (Gyrinocheilus Aymonieri)
• Glass Catfish, Ghostfish (Kryptopterus Bicirrhis)
• Neon Tetra (Paracheirodon Innesi)
• Panda Cory (C. Panda )
• Rosy Barb (Puntius Conchonius)
• Siamese Fighting Fish (Betta Splendens)
• Snails (P. Everettii)
• Suckermouth Catfish (Hypostomus Plecostomus)

200-500 μS/cm:

• Convict Cichlid, Zebra Cichlid (Archocentrus Nigrofasciatus)
• Malawi Cichlids (Aulonocar, Maylandia, Melanochromis and Pseudotropheus)
• Platy (Xiphophorus Maculatus)
• Rainbow Fish (Melanotaen)
• Swordtail (X.helleri)
• White Cloud Mountain Minnow (Tanichthys Albonubes)

>500 μS/cm:

• American Flag Fish (Jordanella Floridae)
• Giant Sailfin Molly (P. Velifera)
• Goldfish (Carassius Auratus)
• Green Spotted Puffer, Pufferfish (Tetraodon Nigroviridis)
• Guppy (Poecilia Reticulata)
• Mosquitofish (Gambusia Holbrooki)
• Sailfin Molly (P. Latipinna)
• Tanganyikan Cichlid (Julidochromi, Neolamprologu and Tropheu)

You can find the full list here.

The conductivity of pure water is almost zero. Your tank water will get more dissolved solids over time due to fish wastes, decomposing fish food, chemicals, medicine and other factors. To reduce TDS, you can simply perform a water change.

If you want to optimize the fish tank water for your fish, then the electrical conductivity measurement features of both the G3 and G6 will be very helpful.

Temperature

The G Series will also monitor the temperature of your fish tank. We find this very important if you don’t already have a dedicated thermometer in your aquarium. This is because, even if your heater comes with a built-in thermometer, it could malfunction at some point. Having a water that is too cold or too hot for the fish you are keeping could cause serious problems if you don’t identify and resolve the problem in a timely manner.

With the G Series Canister, you have another way to keep track of the temperature of your aquarium.

Flow Rate

Last but not least, the HydroTech Performance Monitor will also keep track of the flow rate. Some fish species, such as Bettas, prefer a low flow rate while others, such as the Hillstream Loach, prefer a faster flow rate.

Included Filter Media

Both the G3 and G6 come with the same filter media: Biological G-Nodes (for biological filtration), Chemical Cartridge (for chemical filtration) and Pre-Filter Cartridge (for mechanical filtration).

Optional G Series Filtration Cartridges

Both canister filters also support a few optional filter cartridges. You can check out what each one filters out of your aquarium below:

Fluval G Series Fine Pre-Filter Cartridge

The Fine Pre-Filter Cartridge is mainly for use to filter debris from saltwater fish tank. With that said, it can also be used to provide additional mechanical filtration for freshwater aquariums.

Fluval G Series Phosphate Cartridge

The Phosphate Cartridge will quickly remove up a maximum of 2,200 milligrams of phosphate ion from your marine or freshwater fish tanks.

Fluval G Series Nitrate Cartridge

The Nitrate Cartridge is built to get rid of up to 24,000 milligrams of nitrates ion from your freshwater fish tanks.

Fluval G Series Tri-EX Cartridge

The Tri-EX Cartridge is combines the aforementioned Phosphate and Nitrate Cartridges with activated carbon. Carbon will remove medicine and other chemicals for your tank water. Since you can remove phosphate and nitrates as well, the Tri-EX provides versatile chemical filtration for your tank water.

You can check out the optional G Series Canister Filter Cartridges below:

• Fluval G3 Fine Pre-Filter Cartridge(#CommissionsEarned)
• Fluval G6 Fine Pre-Filter Cartridge(#CommissionsEarned)
• Fluval G3 Phosphate Cartridge(#CommissionsEarned)
• Fluval G6 Phosphate Cartridge(#CommissionsEarned)
• Fluval G3 Nitrate Cartridge(#CommissionsEarned)
• Fluval G6 Nitrate Cartridge(#CommissionsEarned)
• Fluval G3 Tri-EX Cartridge(#CommissionsEarned)
• Fluval G6 Tri-EX Cartridge(#CommissionsEarned)

Quick Release Media Cartridge

Both canister filters in this versus guide also use quick release media cartridges. You can easily access the cartridges by simply opening the top. You can then simply remove and replace.  

Priming Button

The G3 and G6 also features a priming button where you simply press all the way down two or three times in rapid sequence to add water to the canister. So you don’t have to struggle to manually siphon water in the filter any time you decide to clean the inside.

AquaStop Valve Lever

Both models of the G series also take advantage of Fluval’s AquaStop system, which can be used to completely stop the water flow. You can also use the valve lever to control the water flow. Last but not least, you can easily lift the release lever in order to service your canister.

Chrome Plated Cast ZAMA Levers

The G3 and G6 Canisters also use chrome plated case ZAMA levers to seal the canister. The material will not corrode or oxidie even when exposed to saltwater.

Silicone Gasket

The two models from Fluval’s G series also use a silicone gasket. This material is designed to last for a very long time due to its adhesion, flexibility,  low friction, softness and temperature resistance.

Telescopic Intake and Strainer

The multi functional intake valves of the G3 and G6 features a strainer that prevent wastes buildup that would otherwise hinder the water flow. The intake is also telescopic as you can adjust its length to fit the depths of your aquarium.

Spray Nozzles/Spray Bars/Y-Shaped Connector

Both products come with an output nozzle, spray bar and Y-shaped connector. By using the aforementioned connector, you will be able to send the outgoing water from the canister to multiple directions in your fish tank. This will help improve water circulation in your aquarium.

Rim Attachments

The G3 and G6 models also come with rim attachments, which will easily connect the hosing to your intake and output equipment of your canister.

Drive Pump

The drive pump included in both units is built with synchronized dual drive coil, which is controlled by a microprocessor to adjust the start speed, impeller direction, performance and power usage. The pump is also built for durability as it uses an aluminum oxide ceramic impeller shaft in addition to polymer thrust bearing.

Filter Casing

The G3 and G6 also feature a re-enforced polymer inner filter chamber packed inside an ABS polymer enclosure. The combination of these materials results in a leak-proof canister that will also run very quietly.

Video

Resources:

• https://fluvalaquatics.com/us/g-series/
• http://www.fluval-g.com/features_e.php