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Aquarium Canister Filters: The Fluval FX5 Filter

If you’re looking to buy the best, affordable filter for a larger sized tank, be it for a freshwater aquarium, saltwater aquarium or for a turtle tank, the Fluval FX5 is going to be among your choices. It’s a top quality machine, brought to you by years of experience from Fluval filtration.

Hagen has perfected their line of affordable Fluval canister filters over the years, and with the introduction of the 05 series and the FX5 for larger tanks, it’s clear these were designed with perfection in mind. Every need is met, every flaw in former Fluval filtration units eliminated, and every shortcoming in prior design technology overcome.

While the Fluval 105 and 205 works wonderfully on smaller tanks, the Fluval 305 filter and the 405 canister filter cover the mid-sized tanks, the FX5 is the Fluval filtration solution for larger tanks. It is the monster of the Fluval filters, and the top of the line in affordable, large aquarium canister filters. And it’s even more affordable if you buy it online, and most affordable through Amazon.

Fluval FX5 Filter System

Fluval FX5 Filter System

Fluval FX5 Multi-Stage Canister Filter

  • Great for Freshwater, Saltwater or Reef Tanks
  • Smart Pump Circuit Board Provides Optimal Pump Performance
  • Pump Rated at 925gph
  • Circulation Rated at 607gph
  • Self-Priming Instant Start System
  • AquaStop Valves for Flow Control and Easy Removal of Hoses for Maintenance
  • Dual Adjustable Output Nozzles Provide Flow Control and Gas Exchange
  • Professional Grade Materials and Construction
  • Perfected Fluval Design
  • 1.5 Gallons of Versatile Media Capacity
  • 3 Huge, Divided Media Baskets,
  • Low Heat Output
  • Low Energy Consumption at 50-51 Watts
  • 3 Year Guarantee

The Fluval FX5 Filter

It’s a workhorse. Standing 17” tall with a girth of 16”, this monster processes six gallons of water at a time, turning over up to 607 gallons per hour. That makes this aquarium canister filter capable of handling a 150 gallon tank on its own, theoretically. The media chamber houses three huge stacked baskets, which hold up to 1.5 gallons of media in this can.

All the materials used in this are high quality, professional grade, and the design and technology is top of the line. With the Fluval self-priming Instant Start system, Aqua-Stop valves that control flow and allow mess-free hose removal for easy cleaning, Smart Pump technology includes a circuit board that monitors and controls pump speed, high powered motor sealed for quiet performance, automatic daily air purges, features for easy cleaning and maintenance, there’s just nothing missing here. From the wider, redesigned, clog-resistant intake cup to the adjustable twin output nozzles, every part and piece of this Fluval canister filter is designed for maximum functionality and efficiency.

How the FX5 Works

The impeller is housed in the bottom of this unit, and water is drawn up through the outer baskets first. Here it is recommended you place media designed for mechanical filtration of the coarser variety, perhaps growing finer around the top basket.

After running up through the outer baskets the water is diverted back down through the middle compartments. Here is where you really get to customize. If you’re relying on a separate aquarium filter for biological filtration, you can devote all of your center baskets to further mechanical filtration of finer particles and chemical filtration or other type of chemical treatment additive. However with the large media capacity of this canister filter, depending on the size of the tank, you can rely on this canister for adequate biological filtration as well, given the use of proper aquarium filter media.

Fluval FX5 Canister

Fluval FX5 Canister

Tank Capacity of the Fluval FX5 Filter

Okay so the filter is marketed as being capable of effectively filtering a tank up to 400 gallons. I don’t know about that, I’ve never tried it.

The general recommendation is that your aquarium filtration turns over your water at least four times an hour, though sometimes you will hear people recommend 6, 8 or even up to 10 times an hour. Four times an hour is the standard minimum.

Now a problem is in the stated flow rates of the aquarium filters. We don’t always know their exact methods, but it’s generally understood that manufacturers rate their flow rate at a top, unencumbered speed. This means pump speed, not flow rate through a stocked filtration system.

You may get two numbers, a pump speed and a circulation speed. The circulation speed theoretically is how fast water will filter through the filter, however again manufacturers will often test this under best conditions. This means using no filter media, or only a minimal amount, having little head pressure or upwards travel distance for the water flow between the filter unit and the output, and of course using all completely new equipment and materials.

So the circulation speed is a bit more realistic than going by the pump speed, but still not going to be exactly indicative of your reality. Independent testing found the filtration cirulation rate of the FX5 filter in a standard, typical setup to be at about 57% of pump speed, or approximately 525gph.

So when they say the filter is capable of filtering a 400 gallon aquarium, just take that with a grain of salt. All the manufacturers make these outsized claims. I wouldn’t run it on anything above a hundred gallon tank without a supplemental unit such as an appropriately-sized sponge filter.

It should be acknowledged, however, that if the filtration is highly effective, then less turnover will be required. I've heard of people running the FX5 as the sole filtration on tanks as big as 180 gallons with perfect results according to them. That'd give them less than 3 turnovers an hour, but perhaps it is enough.

Watch the Video, Stupid

While it’s not really overly complicated, unless you’re very familiar with aquarium canister filter concepts you should probably watch the instructional DVD which comes with the Fluval FX5 canister filter. Every complaint I’ve heard about the Fluval FX5 has clearly revealed that somebody didn’t watch the video! It’s not a long video, and it very clearly covers everything you should know about using the Fluval FX5.

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And watch it before you set the unit up. Not only will it explain optimal media configurations and cleaning and maintenance features, it will also save you time and frustration by guiding you through the set up. There are a couple of features I either would have overlooked entirely or never quite understood if I hadn’t watched the very helpful DVD.

There are reports from people saying it’s noisy, air gurgling through the system, or who report microbubbles constantly streaming from the output nozzles. There are only two causes for this. Insufficient regular cleaning of the filter or improper setup or valve procedures. Keeping the manual handy to help guide you through the procedures until you get the hang of it is a good idea, too.

So, yes, rare manufacturer defects aside, if your Fluval FX5 is noisy, leaking, or emitting a steady stream of bubbles outside of its daily air purge, all I can say is –in all good natured friendliness- watch the video....

Not the video here, though you can watch that one, too, but watch the instructional DVD which comes with the Fluval FX5 filter. Following the given instructions should clear up any confusion or problems.

Regular Cleaning and Maintenance

Cleaning and maintenance on this filter is about as easy as it gets on a large capacity canister filter. The Lift-Locks let you quickly and easily remove the canister from the hoses. Be sure to follow the instructed procedures. There is generally a small amount of seepage from the hoses when you do this, so be sure to have a rag handy.

If necessary you can drain the can where it is to make it easier to lift. Remove the lid and then the stack of media baskets by lifting out with the 'T' handle. Rinse sponges and other media in removed tank water or other dechlorinated water of nonextreme temperatures to avoid killing off the beneficial bacteria colonies. When replacement of biomedia is called for, be sure to replace no more than half at a time.

With baskets removed rinse out the filter chamber of any collected debris. Replace the baskets and partially fill with two gallons of dechlorinated water. Lock on the lid, return the canister to its position beneath the tank and reattach hoses. Be sure to follow the given procedure for restarting to allow proper air purging.

Semi purgings of loose debris are possible through the purge valve. These can be done in between regular cleanings, but should not be considered sufficient in themselves. The FX5 will also work to drain or partially drain your tank during water changes.


Buy Here Now

I Say Buy the Fluval FX5 Filter, and Do It Online

One of the factors which make the Fluval FX5 filter so popular is its afordability. To find this high quality, reliability, large capacity and powerful performance with the features seen in the FX5 in another filter you'd have to move substantially up in price to an Eheim. The Fluval FX5 may not be quite that good, but it's darned close, and much less expensive.

When buying the Fluval FX5 do be aware that it comes with only the six foam sponges, allowing you to customize the rest of the filtration. You will need to supply additional filter media separately. You need not feel a need to fill each basket, and should fill to no closer than an inch from the top.

The retail price as of May 26th 2010 on the FX5 filter as I type is $399.99, but it’s commonly found for $360 online at Petco and Foster and Smith. Marine and Reef and Big Al’s has it online for $300 right now.

As is often the case, Amazon will get you a better price. You can buy it right now through Amazon for $260.




The Red Baron from Australia on March 06, 2011:

I agree its a great filter for the price. It's a shame it has no UV function. Heard much about Eheim filters? from what I hear 50% of people say Fluval FX5 is better other 50% say Eheim is better.

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