Desired tank turnover rate and FX6 - FX5 canister filters setup

Hi Guys,

I would like to ask your opinion / experience / suggestion please - I am right now upgrading my filtration on 240 gal low tech tank - so far running very well over ten years with Fluval FX5 plus Eheim Professionel 250 - really happy with both - now adding new Fluval FX 6 to beef up ahead of adding Discus to my tank later in March.

My tank is lightly planted now- after I pulled out finally week ago all the heavily growing Valisneria, which was trapping a lot of hard to clean crud and left there only about ten very well grown up Echinodorus varieties easy to clean around. Rest of the tank decor consists from three large pieces of bog wood inside.

My question is on appropriate flow rate and actual current created in the tank - two options being either to connect each FX filter independently in parallel setup (two intakes and two outputs) - than I would get turnover rate of about 8x per h, but I worry about having too strong current in the tank as Discus may not like that strong flow - so I think about putting both FX filters in series (one intake and one output) - from tank to FX 6 - beefed up with PondGuru's FX upgrade kit - coarse + medium foams and rest being 5 kg of his Biohome Ultimate media and activated charcoal layer - from there to the intake of original FX5 - loaded to the max with Biohome Ultimate media only - no foams needed anymore here as mechanical filtration will be taken care of already in the first FX6 filter - and from there back to the tank - this would give turnover rate of about 4.2x per h.

Parallel setup - higher flow rate, full redundancy if something may go wrong with one of the FX filters the other still running full speed- maybe too strong current in my tank? Need to regularly maintain both FX filters.

Setup in series - lower flow rate, partial redundancy - if one FX pump may fail, the second one will be still able to pull the water through both canisters albeit at lower flow rate, regular maintenance needed only on the first FX6 in the series - where mechanical filtration happens - no need to mess up with the second FX5 filter and leave bio-filtration there undisturbed.

Is there anything I might be missing - why the in series setup may not work as hoped for? Or should I not worry about too strong current / flow created in the tank with both FX filters running in parallel setup - plus the Eheim 250 still there as well?

Thank you in advance who may help me with your expert's advice!

Milaz

I would go with what you have now.One FX6 is good for a 400 gal tank.How long is the tank?You will still need to clean the sludge off the biomedia every now and then for the bacteria to have good access to O2.

Here's my 2c.

I have a 200 gallon tank and have TWO Fluval FX6 filters running in parallel. I have both intakes at one end of the tank (each at a different height), and both of the outflows positioned in the center at the back of the tank, with each of the 4 nozzles pointed in various directions (I adjusted their direction and elevation to allow for good flow throughout the whole tank, so I have no "slack" areas). I also have a 1650 gpm powerhead that is close to the surface at the same end as the intakes.

This setup allows for a few things.

1. A very good flow through the tank, but with areas of low flow for fish
that don't like strong currents.

2. The powerhead keeps the water VERY well oxygenated and means I
don't have to run an air pump or air stones (a powerhead is WAY
better for oxygenating the water than a pump/airstones).

3. If either of the Fluval filters breaks/stops for any reason, I have one
that will still keep running and keep the tank in great shape.

4. The rating on the Fluval FX6 is for UP TO 400 gallons, but in reality, it's
not even close to being that if you have done your research. Watch
the Pond Guru's YouTube video on the FX6; I don't buy everything he
says about the FX6, but he is definitely correct about how to correctly
size your tank/FX6.

5. I have both FX6's LOADED with as much Biohome Ultimate as I can
stuff in them. The FX6 has more than enough filtration, especially if
you run 2 of them. What it lacks is as much space as necessary for
bio-media, so I have taken out a couple of the foam filters on the top
of the trays as well as the red trays, and that allowed me to put a ton
more biohome in each FX6.


With the way my tank is set up, I have:

15 Discus between 4.5" and 6.5", 40 Cardinal Tetras, 11 Buenos Aires Tetras, 11 False Julii Corydoras, 2 bristlenose Plecos, 15 Otocinclus, 30 Filligree Tetras, a random Tetra of indeterminate type, 80 Nerite snails, a random black and yellow Catfish on unknown type, 20 Siamese Glass Catfish, one HUGE Chinese Algae eater, 5 German Rams, 12 Viper Shrimp and around 25 Malaysian Flower shrimp.

My water parameters are perfect. 0 Ammonia at all times, 0 Nitrites at all times and a MANAGED 5-10 ppm of Nitrates, since my tank is fully planted. I do one 75% water change per week and the tank is thriving way beyond any expectations I had for it.

Cheers.

Thank you so much for sharing in such great detail your well proven and working setup.

My tank dimensions are 195 x 70 x 65 cm - and I have it up and running perfectly for ten years as Amazonas biotope community tank - no diseases ever, no algae issues - just recently got fed up with Valisneria furiously growing and so dense so it was hard to clean so I got it all out - suddenly much bigger tank visually - great space for Discus now.

I will follow your advice and setup botn original FX5 and new FX6 independently as clearly in your similar setup you do not have any issues with too strong current I feared - the same setup as well on one side filter intakes - different heights - and on the other both returns - so the tank will work as river flow from left to right.

I am following PondGuru (Richard) for many years - as I also have outdoor aquarium - 24.000 L Koi pond - and he has some very good filter ideas for this - he has send me earlier this week my order of two of his FX5-6 upgrade kits - foams and Biohome Ultimate media - hope to get it by end of this week to finalize both FX filters setup and start maturing the Biohome Ultimate media asaap - utilizing my original Eheim Substrate Pro ceramic media from my original FX5 as the top trays in both FX filters to seed new Biohome Ultimate media properly.

How long did it take you to establish the full nitrogen cycle - both nitrification but especially the denitrification part done by facultative anaerobes inside the Biohome Ultimate? Richard is talking about up to six months - I have seen about four months of the same in my pond anoxic filter as well as in the Ogata Crystal Bio media I use in my pond shower filters - so hope it will be fully cycled by summer - but would not be so patient with Discus addition - would like to have them in about two - three weeks - as my aquarium is long time fully settled - so addition of third filter (new FX6) will not disturb but improve further the balance.

Once more thank you for your promt and very encouraging response.

Quote:

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Originally Posted by Milaz

Thank you so much for sharing in such great detail your well proven and working setup.

My tank dimensions are 195 x 70 x 65 cm - and I have it up and running perfectly for ten years as Amazonas biotope community tank - no diseases ever, no algae issues - just recently got fed up with Valisneria furiously growing and so dense so it was hard to clean so I got it all out - suddenly much bigger tank visually - great space for Discus now.

I will follow your advice and setup botn original FX5 and new FX6 independently as clearly in your similar setup you do not have any issues with too strong current I feared - the same setup as well on one side filter intakes - different heights - and on the other both returns - so the tank will work as river flow from left to right.

I am following PondGuru (Richard) for many years - as I also have outdoor aquarium - 24.000 L Koi pond - and he has some very good filter ideas for this - he has send me earlier this week my order of two of his FX5-6 upgrade kits - foams and Biohome Ultimate media - hope to get it by end of this week to finalize both FX filters setup and start maturing the Biohome Ultimate media asaap - utilizing my original Eheim Substrate Pro ceramic media from my original FX5 as the top trays in both FX filters to seed new Biohome Ultimate media properly.

How long did it take you to establish the full nitrogen cycle - both nitrification but especially the denitrification part done by facultative anaerobes inside the Biohome Ultimate? Richard is talking about up to six months - I have seen about four months of the same in my pond anoxic filter as well as in the Ogata Crystal Bio media I use in my pond shower filters - so hope it will be fully cycled by summer - but would not be so patient with Discus addition - would like to have them in about two - three weeks - as my aquarium is long time fully settled - so addition of third filter (new FX6) will not disturb but improve further the balance.

Once more thank you for your promt and very encouraging response.

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It took my tank around 5 months to get the full cycle established. I was able to go from 4 X 75% water changes per week to just One. As I stated, my Ammonia and Nitrites are zero, always zero, and my Nitrates I want to be around 10 ppm, so my plants flourish. The tank is completely stable; no Ph swings, no spikes of any type, it just runs extraordinarily well.

When I first set up the tank, I used a TON of existing Biohome Ultimate from another of my tanks, in the two Fluval FX6 filters, and it was pretty much cycled (not complete full cycle) in two days.

I have kept Tropical fish for over 25 years, and I like my present setup the best of all the filter/media setups I have had over the years.

Cheers, and good luck, I think you will be very happy.

Thank you for sharing your great setup - and encouragement. While I have grown up with discus as my father had two tanks 480 L each with them in my room when I was growing up and I had aquariums since I remember (now 40+ years in this hobby), this is my first into discus myself so I really appreciate all the great advice from this forum.

Quote:

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Originally Posted by Milaz

Thank you for sharing your great setup - and encouragement. While I have grown up with discus as my father had two tanks 480 L each with them in my room when I was growing up and I had aquariums since I remember (now 40+ years in this hobby), this is my first into discus myself so I really appreciate all the great advice from this forum.

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P.S. Here is my tank, just so you can get an idea of what it looks like, and the positioning of the inlets/outlets and the powerhead.

Right click on the image below and say "open in a new tab" and it will display larger!

Attachment 122978

Wow - your aquarium is gorgeous - with really impressive plant growth - and your discus seem really happy and enjoying it there!

I have just installed the new FX6 in parallel setup following your advice - current is OK - well distributed along the tank. Just Biohome Ultimate media from Richard aka PondGuru did not arrived yet - he shipped it on 6/3 - so hopeffuly by mid next week it arrives - so I used the original ceramic one supplied by Fluval with FX6 - plus added activated charcoal to cleanup any traces of chlorine and heavy metals ahead of next Friday - when I am going to pick up my first 10 turquoise discus from best local breeder about 150km away.

I have started new FX6 this afternoon- all is working fine - but it is noticeably louder than the original FX5 - standing next to it - runnibg flawlesly for over 10 years - this has surprised me - why the hell did Hagen messed up with the pump motor? I would rather like it as quiet as the FX5 is - even if at the same power consumption - 7W higher than new FX6 is rated - I wonder if pump motor from FX5 can be fitted on FX6 as well - not only it is noticeably quieter - but also pumps 200 L/h more!?!

Quote:

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Originally Posted by ggillies

P.S. Here is my tank, just so you can get an idea of what it looks like, and the positioning of the inlets/outlets and the powerhead.

Right click on the image below and say "open in a new tab" and it will display larger!

Attachment 122978

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I love your tank! So clean and bright! I just had to save the image to give me something to work towards haha. What sort of substrate are you running?