Thanks for the easy to follow setup video. I spent way too much time trying to set it up following the directions. When I found your video I was up and running in less than 15 min and was confident I was doing it right . Thanks

Installed an FX4 for my 33L tank. I know it's Big Time Overkill but it's an unbelievable filter, and the fish seem to love it. Setting up a 125 with an FX6. Can't wait to see how that one works. Being a true believer of Fluval products, I can't expect anything but a very clean and healthy tank. Thank you KG Tropicals for always providing honest and precise videos we all enjoy and benefits from. Sending you Tons of Aloha from Hawaii !

"overkill, never a bad thing" this guy is my new expert.

I have the FX4 on my 75gal tank, my Oscar and both Pleco’s have thrived the past year with it. I did ad a power head with a polishing filter for it. Love my FX4

Where to start. This is a good canister filter, however, the marketing is a bit misleading. 1. There are only 3 stages of filtration: Mechanical, biological, and chemical. They break out the filtration into 5 sections. With that said, a lot of aquarists don’t use carbon. I threw my carbon pad away. Marketing = 5 sounds more impressive than 3. 2. The actual compartments that house the bio-media are very small. This means that you aren't going to get a lot of bio-media in this canister filter. The same problem with the FX6. Secondly, the bio-media that is supplied with this filter are ceramic rings, which are ok, but, by no means great. There definitely isn’t enough bio-media to filter a moderately to heavily stocked 250 gallon that it says its rated for. Some would argue that the copious amounts of sponges will house beneficial bacteria, and that is true. Good bio-media has more surface area than sponge however and would hold more. 3. The output of the FX4 is NOT 700gph. Filter makers commonly rate the output of their product based on an empty filter (without media) running with no head height. In other words the output of the filter is measured right at the empty canister filter output, without a hose attached. If one were to fill the filter with sponges, filter pads, and bio-media and then attach a hose to the output and pump it up 4 feet up into a tank, that 700 GPH quickly gets CUT IN HALF. 350 gph would be a more realistic approximate rating. Again, marketing. Be careful how the product is rated. Note: The manual rates this truer output as "filter circulation" at 450gph. It goes on to state that the filter is empty and the input and output hoses are of the same length, but, do not specify what that length is. 4. Not sure where there is the idea that there are 5 baskets. There are 2 primary white baskets with 2 red baskets that fit inside the white baskets and do little more than take up space. I discarded the red baskets as they are useless. Again, marketing. when looking at other canister filters, other manufacturers have additional baskets that actually do hold more media. Sadly, the FX4 has 2 primary baskets and the compartment that holds the bio-media is small. In conclusion, IMHO, the FX4 is hyped-up, with a true flow rate of somewhere around 350-400gph. Its construction is first rate. I’d like to see them reduce the volume of sponges and increase the bio-media compartments. Id also like for them to get rid of the red baskets, and, replace the hosing with flexible, non-ribbed vinyl hose. The intake tube basket is also a bit cumbersome and is an eyesore in the tank. Redesign that input tube to make it more streamline, and, add a pre-filter intake sponge.

thanks for sharing friend, one main thing is that you are enjoying the hobby, yes it's through a bad situation but after the fact is to continue to enjoy our tanks. have a great week pal.

Setting up my Fluval FX-4 was SOOOOOO much easier than the Marineland 360. I'll only use Fluval for now on!! No leaking, not noisy, no water on the floor, etc.

The fx4 isn't near big enough for a 125 gal aquarium alone. Fluvals claimed 700 gph is measured with the canister empty, with zero filter media inside and no head space. With the correct amount of filtering media inside and your typical 2-3 ft head space, that 700 gph number will be easily cut in half and actually probably more,, making its output (at best) 350 gph. That means with ideal conditions and with brand new clean media the best someone can expect this canister to turn over a 125 gallon tank is only 2.8 times and hour. And as the filter media gets more and more dirty before being cleaned, that number will continue to go down. In all actuality, for a 125 gallon tank you'd need 2 fx4's. Even one fx6 is just barely enough for a 125 gallon aquarium.

I just put one in my 75 gal. Great video. My silver dollars are so happy I got rid of my top fin pets mart garbage canister filter.

Yes, let's see the fx-6 clean out video. Great video on the fx-4.

I was skeptical about the Fluval fx4 but after watching your video you changed my mind. Thanks glad i saw this video.

Yes on fx6 cleaning. !! I have fx5 and fx6 on 150 ac tank and haven't cleaned either yet , been running since may 27 lol

Nice Overview of the FX4 John, love your channel, looking forward to seeing the discus getting back into there original tank. Keep up the good work :-)

Just ordered myself a FX-4 my first Fluvial filter, cant wait to try it out.. Thanks for the video.

I use two FX6s on my 120 African Cichlid tank. Way overstocked. The tank is perfect!

THANK YOU so much for your video!!!!! I just upgraded my marine360s to an FX4 because of your video

I'm getting a FX4 for my 60 gallon...Thanks for the info

Do a show showing a pre canister before your canister, adding lots of bio material, they sell some nice ones

Great Video by you . I too would like to see you clean your Fx6..... Thank you

Yes clean it out. I wanted to clean mine out when it reach a year. I wanna see the steps you take cleaning it. February will be a year. I may need to change my sponges as well. The water flow is not what it use to be.

Thank you for the effort and easy direction.

You should mention the fittings on the bottom of the canister are for the fluval vacuum which is another outstanding Fluval product

That argument between the parrot and the Oscar though.

Got an fx4 on sale for a 120 gallon. Excited to see how it does!

Yes please show us how you clean your fx-6. As always great video! Can't wait for the new discus tank!

yes let"s see the fx-6 clean out video great video john on the fx-4 and thank you for sharing with us

Id like to see a maintenance video of the FX series filters. I just had one of my hang on the back filters go back so I upgraded to an FX4. Its so quite!

Excellent infos. I am working on my next project and this helped me take down info on those. I would like the Oase too but hard to find in Canada and much less knowledge on those here. Fluval is so well known. Thanks for the coaching and demo.

Terrific video, very well done. Thank you!.. going to buy one for my 125 gallon Central American cichlid tank.

He is correct, you want to turn it over about five times but just because it says 750 gallons an hour does not mean it has all the media in it and has been used. So you should always cut that number in half.

Just a heads up on the spray hose In to the tank after 12 hrs it turns off and when it starts it kicks pretty hard one of my hoses came off and water drained all the way down it happened when I was sleeping .. I added clamps on that hose as well after that accident I have 3 fx6s and I love it great product

Show Us how to Properly Clean the Fluval FX6 Canister Filter. I Can't Wait Sir. I Just Bought One a Couple Of Day's Ago.

I would actually like to see the FX4 clean out video....thanks 👍

You don't have to order a new hose because you cut one too short. They make hose barb unions that join two hoses together.

Just bought the FX4 for my 75 gallon and fixing to set it up so that’s why I’m watching this video to show me visually how to install and start up this filter. Also where did u def the driftwood in the tank behind u

thanks very helpful running 2 fx4 on a 125 gallon

I would like a maintenance video and a water change

nice video on the new fx4! also awesome shout out to the house of tropicals in Glen burnie. was just there Saturday afternoon. will definitely keep an eye out for you. considering it's probably like a 2 1/2 hour ride you probably don't go to often.

Hi John, Great video. I have been watching many of your videos. They are informative, gives a great direction and you are absolutely sincere and honest. I am from India and I use a sunsun 302 for a very small 25 gallon gold fish tank. I understand it's sold as Aquatop in the US. In addition, I have an air pump with some mechanical filters. Do let me know according to you how is the biohome ultimate (pondguru videos). Will appreciate a video on your recommendations on media to be put in filter. Thanks

Would still love to see the video of cleaning out the FX6

I have a sand base aquarium, as regards to filter intake you could always use a litre coke bottle cut it in half and put the intake inside the bottom of the coke bottle and put some filter floss inside the bottom of the bottle with the intake. Do think that would be ok?🤔

It may be my bio load but my fX4 got so dirty within a couple weeks on my 125 gallon. I bought the fX6 for the 125 and put the fx4 on my 90 gallon.

yes. i would like to see a cleaning of the fx6.

I want to see the fx6 clean up. Like the black stand. Good setup

i have the fx4 on my 75g oscar tank and love it its so quite only way i could tell if its running is by looking at the outflow lols

This rim connectors were a pain for me and are what made me realize I was using a reptile tank instead of a fish tank! Luckily it was a turtle tank so it was meant to hold water but none of the HOB attachments have ever worked for me because the plastic rim is larger than a normal tank.

Those hoses should have no droop in them, you will be able to purge all air if those hoses are cut a little more and go in a straight upward angle, you will achieve better flow as well 🖒

Could you make a video on water change and maintenance on the FX4?!

There's no overkill when setting up a FX4 on a 125...actually, a more realistic approach (and I have learned this after advice from more than 2 well experienced fish keepers) would be cutting the advertised flow in half and then divide that by 3 and there's the biggest tank you should be using these filters on...a FX6 is more adequate for your 125 and up to 150 gallons. I realize this video is 5 years old; now, but for newcomers, they need to know how to use those canisters, properly. Love your content, though. Still, it's best to do in depth research to prevent much avoidable mistakes. Fluval, indeed, is a powerhouse when it comes to products for fish keeping.

would love to see you cleaning the FX 6 or any of the FX series

I suggest fluval R&D to make the hosing rework so that it can fit in chinese (minijiang, sobo etc) tanks also, although the filter is superb

would be nice to se cleaning of your fx6 :)

I have a 75 gallon with a tidal 75 and sponge filter I only have two chiclids. I want to get a fx4 so I can add more chiclids how can I add it with out losing too much beneficial bacteria.

John love the videos, look forward to watching. Ordered some of your food, excited to try it!!! Also have a extra PEPSI for me. ha

Please do the cleaning. Part. Just got my Fluval FX4. Ty.

When it says 700 gallons per hour is without any filter media. with filter media it's 450 gallons per hour

I get this is supposed to be enough filtration for a 125 but I just saw you make a video with an fx6 on a 75. And I've seen people with 125 gallon or higher go with 2 fx6 for theirs. Maybe everyone is crazy over filtering who knows. I'm thinking of upgrading to a 75 later in the yr with cyclids. I was thinking fx6 but now I'm stuck between fx4 or fx6. I woukd like to have enough filtration to overstock if it ends up helping with less aggression.

Sand looks great in there!

What about the O-RING? Why no mention of the O-RING? Very important.

Please do a video on how to maintain the motor on the FX6!

hmm, weird. this video didn't show up in my sub box but was showing on my home screen. glad I caught the vid

What do I do if my fx4 is not pumping any water but could still hear the impeller running? Please help .

Why would you try to limit ammonia with ammo-chips during cycling a tank? You want to feed the bacteria with lots of ammonia to grow the largest colonies.

I just bought this filter and its not pumping water through the intake and hardly pumping water through the outtake .Please help

Great video 👍😁 Greatings from Poland.

So just picked mine up and set it up. Well got to excited and forgot to add one of my media bags. Anyway. How to u de pressurize this thing? Just spilled about a gallon or two on the floor

Hi John can you show if you know how looks water flow inside FX4 or FX6? I would like to put Purigen inside and I wondering where is final filtration inside / final, before water will leave canister?

I wish I had gone with a fluval. Always kinda been afraid of buying a used one and at the time I wasn't willing to dish out the money for an fx6 so I bought a c530 and i have issues with it everytime i clean it.

Love your channel thank you very much for your help

How is this fx4 holding up in the 125? Or would you recommend an fx6 for a 125 long?

I’m fairly new and about to change over to canister opposed to hang over fluvals. Have 125 gallon. Is this still beat filter to get? Video I see is old

I just got an fx4 for 55g grow out tank.

How much water do you add to the FX 4 before restarting after maintenance? Oh, about 2 gallons - THANKS John!

We just hooked one up yesterday and works great but keeps making a swishing nose every few seconds- that normal?

Wait just watched this you put your in and out at different ends of the tank? Are you suppose to do this?

Great insight thank you

Need the 6 for that size or two 4s

Love all your videos! I cannot find the answer to this anywhere and maybe it’s a simple one... when my fx4 primes 12 hours after I’ve cleaned the tank that day, it pushes out TONS of fish waste. Seems like everything that the filter brought in 12 hours is getting pushed right into the tank when it comes back on. It doesn’t do this when it first comes on and primes after cleaning. Only the prime sequence it does after the first 12 hours post filter clean. I am following all the directions for the layering of media. I can’t find anything about this online.

I'm running two FX4 on a 120 gallon tank...

Do the ceramic tubes have to be in filter bags? I noticed you didn't put them in bags but you did put that other stuff in bags.

im getting a 75 gallon, and frankly im a bit lazy on cleaning, plus dont want to have to lug a bucket around. would the 4 be to much overkill?

My FX4 won’t stop throwing bubbles into the tank

i agree about what you say with Cichlid tanks, is this overkill for a goldfish 60 gallon tank?

I'm having problems figuring out how many gallons my bow front is. I've gotten such a variation in numbers I'm just as confused now as when I started. Tank is 48" x 23" x 12" at the ends and 18" in the middle. Please tell me how many gallons it is. Just started the FX6 last week in it and want to know if I should get a smaller canister. The tank is home to Balla's, Roseline's, Odessa barbs, two catfish and a bristlenose.

Mines didn’t provide enough oxygen my Arowana almost died I had to install my old hang back on there too

Thanks John.. great vid! I enjoyed!

Would you use a canister filter on 135 gallon tank 6' x18" high x24" deep or (2) Seachem Tidal 110 filters ? I plan to grow plants in the new tank . Thank you

Yeah do a video cleaning it.

Be sure to note that the pump is rated for 700 gph, but the filter circulation is actually 450 gph.

Hi there, love how you explained. I have a question. Can you control how much water to flow/filter?

So I would be safe with the FX4 on a 60g overstocked Peacock/Hap tank

Hi, thanks for all the videos. Just to understand, the fx6 was too much for the 125.? Thanks

Awesome video , was trying to decide between a fx4 or fx6 and gonna go with the fx4

Can fx4 can be used for 50g tank 190 lts goldfish tank

Woody's Discus (FB) I am having a 150 gallon tank and stand make at this point in time. Only have a EHIM 2217 on my tank now, With a HOB filter and a sponge filrer. I am sure the fx4 wiil be enough filtration, but as they say in the discus world "you cannot over filtrate a Discus tank. (same with other Cichlids). What is your take ? Woody.

Hey I need your input desperately! I recently jumped into doing African Cichlids and my old 407 (used for angelfish previously) just wasn't cutting it for a 75 so I decided to get an FX4. It seems to be quite a bit louder (deeper sounding) than the 407. How would you rate the noise level of this filter in comparison? I wonder if I got a bad motor. I don't want to switch back to the 407 but it seems odd how loud this filter is in comparison.

Your first mistake is going by the up to.., in gallons… the up to 400 gallon for a 150 is in my opinion ( depending on what you stock( salt water fish) could still be to small, not enough pour bio filtration anorobic

Hi for 184 gallons what do you suggest? Fx4 or Fx6?Thanks

I'm starting a new 125 gallon setup goin to be a few bottom feeders what would be the best for bottom ....gravel?

How can I get the most out of my fluval fx4 I have it on my 125gal but my water quality can still be a lot better. Water is currently a 7 out of 10 will amochips help