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6 Gallon Nano Tank with Anoxic Filter Plenum (UGF)


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So...

I going to be setting up a pair of 6 gallon nano tanks for display in a Ikea Kallax bookcase.  The Kallax looks like the attached pic.  The "cavities" in it measure 13" x 13" x 15" (deep), and the tanks I will be using measure 11.5" cubed. 

The intended inhabitants are to be soft-water nano fish (a dozen neon tetras in one, a dozen chili rasboras in the other), plus lots of shrimp and some nerite snails.  Plant life will be Pogostemon Stellatus Octopus (background), with some Water Sprite for the mid-ground and moss balls scattered.

Here are the details of the build:

  • (2x) Aqueon Frameless Cube tanks - 6 Gal. each
  • (2X) Fluval Plant 3.0 Nano Lights
  • (2x) Aquarium Coop Nano Sponge Filters
  • (2X) Penn-Plax UGF plates (the set intended for a 10 gallon aquarium is 2 plates measuring 9.5" each, so one in each), set up in a slow-flow plenum configuration
  • (1X) Tetra AP60 air pump (definitely bigger than required, but I wanted dual outlets, and this is the smallest one that has them) to supply the plenums and sponges
  • (2x) auomii Mini submersible heaters, 50W (again, bigger than needed, but I had these laying around)

Substrate will be a mix of Fluval Stratum (for water softening and the shrimp) and Seachem Flourite Red (for the anoxic setup - details to follow), plus some Seachem Matrix Bio-Media for under the plenums.

The goal is to establish a bio-system that requires very limited water changes, and a reduction in supplemental plant fertilization.  I've had great success with this in my Walstadt Method setups, but I wanted to try something new. 

I'm a fan of "fish-centric" aquariums (I don't enjoy the details of being an "aquatic plant farmer").  The methods used in most setups is to heavily plant and rely on nitrate feeding by those plants (along with supplemental fertilization) to keep the environment stable.  I'm not a fan of relying on plants for this, IMO you become a slave to them - and not the other forms of life.

The theory here is to let the anoxic filter consume the nitrates, and feed the plants with ammonia (which they greatly prefer anyway).

Stay tuned...

61Un+NYv0bL._AC_SY879_.jpg

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Posted (edited)
3 minutes ago, Fish Folk said:

Interesting! You may want to be sure they’re easy enough to get into from the rimless top. Otherwise... pulling them out to fish stuff out is not fun.

The tanks are going into the two cavities that are the second layer from the top.  I have a table the matches the height of the base of that level.  I can just pull that table in front whenever necessary, and slide the tanks out, no lifting required (they will only weigh ~50lbs each).

Edited by tonyjuliano
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2 minutes ago, Patrick_G said:

This sounds like a fun experiment. Do you plan on keeping the sponge filters long term or just to get things started? 
 

Also, the leveling pads supplied with the Aqueon cubes stick the tank to whatever surface they’re on. You might consider some sort of buffer material between the tank and the shelf. 

I'm hoping that the sponge filters will not be necessary long-term, but if need be I have no problem with them staying in place.  The nano size sponges are very small and easily concealed.

I've already addressed the "sticky-ness" of the foam leveling pads by placing a layer of felt underneath.  Full tanks slide in and out easily.

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Oh…. And speaking of the tanks chosen, I had originally spec’d out a pair of 30cm low iron rimless cubes (7 gallon) for this project, but the Aqueons went on crazy sale at Petco (10 bucks a piece!).

But, as the old saying goes - you get what you pay for.

Workmanship is kinda crappy, glass is thin.  I had to spend over an hour with a razor blade to remove excess silicone from everywhere.  I’ve always found Aqueon to be a “budget brand” at best.

If I had to do it again, I would probably shell out the extra $60 per tank for quality, but these will do for now.

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4 hours ago, tonyjuliano said:

I'm hoping that the sponge filters will not be necessary long-term, but if need be I have no problem with them staying in place.  The nano size sponges are very small and easily concealed.

I've already addressed the "sticky-ness" of the foam leveling pads by placing a layer of felt underneath.  Full tanks slide in and out easily.

Thanks! I’ll be poaching the felt idea. 😀

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And here is how it starts, with a pair of 6 gallon cubes.

IMG_0565.jpg.4f83c3c9a8565ec863d304af25141be4.jpg

This is the Penn-Plax UGF set intended for use in a standard 10 gallon setup. They are meant to be "clipped" together for use in that situation, but for this project they will be used individually.  The lift tubes you see at the top of the pic will have to be shortened dramatically to achieve slow-flow, and the other items shown (less air stones) will not be used.

IMG_0564.jpg.bd0f7f94884c922dbd3ae65c12a576bb.jpg

Layer 1 is Bio-Media, which is put in place below the filter plates.  Shown below is a mixture of Seachem Matrix, Fluval Bio-Tubes & Eheim Substrat (all utilized because I had them laying around).  Use your Bio-Media of choice.

IMG_0566.jpg.56bb87043302d0fb8cfc1064218e0e15.jpg

Layer 2 - Here is the filter plate put in place over top of the Bio-Media, around the edges, I've place my intended final substrate layer, which is Fluval Stratum.

IMG_0568.jpg.6932ad43875cc61e0df4daf074c6b7dd.jpg

As I mentioned earlier, the lift tubes need to be shortened in order to achieve slow-flow through the UGF.  Instead of multiple gallons per hour, we are looking for more like 1 or 2 gallons per hour.  As such, I've cut the lift tubes to a height of 2 inches, which is the distance above the plate that i want the surface of my substrate to be.

IMG_0569.jpg.72ca2eeb1485eecfe5c94f054c5ec731.jpg

I purchased some 1" dia. plastic caps from Amazon in order to make my own lift tube tops.

IMG_0570.jpg.88926e7d18aeea7d3f20cf3887fde92a.jpg

In these I drilled a central hole (tight fitting) for the airline to pass through.  Surrounding this hole. I drilled a number of small holes for bubble flow.

IMG_0571.jpg.b4e85361744d14bf7a1374e65672c70c.jpg

Then the airstone was attached.

IMG_0573.jpg.d5dc3d00f8638f7a9ea59f7b51cdc152.jpg

Layer 3 (on top of plate) is the iron source.  I've used Seachem Flourite Red.  You can use Laterite (much less $), if you can find it, I couldn't.  This is important, whatever you choose for this layer it must be clay-based and iron-rich.

IMG_0575.jpg.ab6800db2dfef30baa46bc9cd8d3e0cd.jpg

Final layer - You cap the whole thing off with your final substrate of choice, in my case that is Fluval Stratum.  This was chosen because of my intention to house softer-water fish (Neon Tetras in Cube #1, Chili Rasboras in #2, along with lots of shrimp.  The PH of my tap water in on the "higher" side (~7.8) so this substrate will help with that.

IMG_0576.jpg.0c84e6e7f31264688169c6201acb5dd2.jpg

That's it for the layering, next up will be installation of the Nano Sponge Filter and running the airlines.

Much more to come, stay tuned...

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Posted (edited)

Here is the "right side" tank with the nano sponge filter and airlines run:

IMG_0579.jpeg.a6927e97fc44c2c0667bcc7a8b7768ff.jpeg

I buried the airline to the UGF plate...

IMG_0580.jpeg.2636860f5699f00ede177954bc0187e9.jpeg

A word about Aquarium Coop's Sponge Filters.  They are excellent.  I'm not a huge fan of sponge filters, but thess are of excellent design.  Weighted base, coarse sponge, it's the small details that make a difference for me in any product.  Coupled with the Ziss Never Clog Airstones, these are hard to beat.  

IMG_0582.jpeg.800b0f9e61fa69db5520f3c58f635b68.jpeg

Airlines for both are run through a 2-way gang setup, that has an integral check valve.

IMG_0578.jpeg.be6d2646f469f728d2fcf795495bd360.jpeg

 Next up normally would be hardscape, followed by plants and fill, but this setup needs an extra step. 

Both the Seachem Flourite Red and Fluval Stratum substrates are extremely "dusty".  Normally one would have to rinse forever prior to laying them in, and and they would still cloud things up.

But I have something different planned, stay tuned for the next step in this process.

Edited by tonyjuliano
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Posted (edited)

This is what Fluval Stratum does, sans rinsing (it doesn't get much better if you rinse it, either!)

IMG_0584.jpeg.639ccdda341e207cd0b33942cdc541ff.jpeg

Enter my "secret weapon", the Marineland Magnum water polishing filter...

IMG_0585.jpeg.ee1e8ba5f2ad294da2b713d250f9ef09.jpeg

It's an internal filter that comes with a 5-micron pleated cartridge.

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You can even increase its capability by charging it with diatom powder, for super filtration, but that won't be necessary in this instance.

After only 10 minutes of run-time...

IMG_0587.jpeg.8204275584a9dd03089caa906558770f.jpeg

Next I'll empty it again, tidy up the substrate and start laying in hardscape and plants.

Look for it...

Edited by tonyjuliano
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Posted (edited)

Hardscape & plants (Pogostemon helferi, water sprite & octopus from my grow out tank), laid out (sans water), I'm not much of an aquascaper - I'm afraid.

IMG_0589.jpeg.9a7c49bd193de34c54692112e1e5e770.jpeg

Added heater, water, cover & lights.  Finalized all the airline connections & fired it up.  It's a little cloudy, but not from the substrate this time.  it's full of air bubbles that need to gas off.

IMG_0590.jpeg.8dad34e3969218cab2d6c08ba8e8824e.jpeg

Here's more of a front view.  I'm running the air to both the sponge & UGF at full throttle, just to "bed" everything in.  I'll let it go like this overnight, and turn the UGF flow down in the morning.

IMG_0591.jpeg.9928fdbd718cafe761049ae83c4fa04e.jpeg

One more thing for now...  Seeding the water column with ammonium chloride to feed the plants and start the cycle.

Now the fun part begins.  Over the next couple of weeks I'll take measurements every day to see how the cycle is setting up, and if this slow flow plenum can really control nitrates like hypothesized.

IMG_0592.jpeg

Edited by tonyjuliano
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I am intrigued and will be watching this thread closely.  I think your test coupled with the one I am proposing would shed a lot of light onto UGF used 2 different ways and see the results unfold in real time. 

Question....your theory is your setup will cause an anoxic environment under the plate but wouldn't having oxygenated water flowing even in as little as 1-2 gal per hours keep that from happening? The bubbles from the UGF would keep the water oxygenated.   

Back when the first "denitrators" came out

sera Bio-Denitrator - Sell off/Pasar Malam Shop - Singapore Reef Club - The  number one resources portal and community for all saltwater reef aquarium  keeping hobby in Asia. 1990 ish they were run slower than 1-2 gal per hour otherwise we were not seeing any results. we had to slow the flow way down...literally we were counting drops per min entering the thing. The we started seeing some results. 

I am not an expert just explaining my experiences with anerobic/ anoxic filters.  Again I am very intrigued by your setup and I hope it exceeds your expectations.

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8 minutes ago, ARMYVET said:

Question....your theory is your setup will cause an anoxic environment under the plate but wouldn't having oxygenated water flowing even in as little as 1-2 gal per hours keep that from happening? The bubbles from the UGF would keep the water oxygenated.   

Well, it's not really my "theory", most of this is based on the work of Dr. Kevin Novak.  He's had a lot of success setting anoxic filtration in ponds and the sumps of larger aquariums using baskets filled with clay and an iron source.

I'm just trying to test it at a smaller scale (much), using a method he described recently (slow-flow UGF with clay/iron source).

His work has been met with a lot of controversy and resistance, as it flies in the face of accepted dogma from the "uber planted tank" crowd, but I think his science is sound so I wanted to test for myself.  I have a background in wastewater management, and all this makes perfect sense to me.  He thinks, and I largely agree, that too many people in this hobby are raising and tending plants primarily, with little in the way of fish life. 

As far as oxygenation, the water column will continue to be oxygenated (you couldn't have any fish if it wasn't!), but the area under the plate SHOULD be severely oxygen deprived ("should" being the hopeful word, here), by lack of flow and some mysterious interaction of the clay/iron.

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4 minutes ago, tonyjuliano said:

Well, it's not really my "theory", most of this is based on the work of Dr. Kevin Novak.  He's had a lot of success setting anoxic filtration in ponds and the sumps of larger aquariums using baskets filled with clay and an iron source.

I'm just trying to test it at a smaller scale (much), using a method he described recently (slow-flow UGF with clay/iron source).

His work has been met with a lot of controversy and resistance, as it flies in the face of accepted dogma from the "uber planted tank" crowd, but I think his science is sound so I wanted to test for myself.  I have a background in wastewater management, and all this makes perfect sense to me.  He thinks, and I largely agree, that too many people in this hobby are raising and tending plants primarily, with little in the way of fish life. 

As far as oxygenation, the water column will continue to be oxygenated (you couldn't have any fish if it wasn't!), but the area under the plate SHOULD be severely oxygen deprived ("should" being the hopeful word, here), by lack of flow and some mysterious interaction of the clay/iron.

Again you have intrigued me further and will read up on DR. Kevin Novak.  I am always interested in learning new theories and expand what I think I know...LOL

 I could see if the tank was much much larger that 1-2 gal per hour would be slow flow but in a 6 gallon tank maybe even 5 gallons when you factor in substrate and hardscape....at 2 gal per hour your sending 30-40  percent of total water volume thru the UGF.  Do you feel that is slow enough to have anaerobic bacteria thrive to create the anoxic environment your seeking?

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Posted (edited)
2 minutes ago, ARMYVET said:

Do you feel that is slow enough to have anaerobic bacteria thrive to create the anoxic environment your seeking?

Nope, I don't.  I was using this flow rate as a starting point (it's what Dr. Novak demonstrated in a 20 gallon aquarium).

I fully anticipate I would need to slow it down even further, but that's what testing and observation is for.  I don't know if it will be even possible, but there's only one way to find out.

The "plan", right now, is to establish a traditional cycle, then try to attain anoxic condition.

Edited by tonyjuliano
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1 minute ago, tonyjuliano said:

Nope, I don't.  I was using this flow rate as a starting point (it's what Dr. Novak demonstrated in a 20 gallon aquarium).

I fully anticipate I would need to slow it down even further, but that's what testing and observation is for.  I don't know if it will be even possible, but there's only one way to find out.

Ahhh I completely understand and you are so right.  Until you try how do you really know.  Too bad we cannot measure the actual flow.  I bet those numbers would be very surprising using the air stone and your cap on the short lift tube.  

Wil you be doing the plants with ferts and if so what kind and what will your schedule be?

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Just now, ARMYVET said:

Wil you be doing the plants with ferts and if so what kind and what will your schedule be?

As you may have noticed, the plants selected are all "low tech, slow growers".  They will get plenty to feed on from the ammonia-dosing initially.  After normal cycle is established, my nitrates should start to climb beyond what they can consume (this is where I will see if the whole "anoxic theory" can work.

If "nirvana" is achieved, and all excess nitrates are consumed by something other than plant matter, then I'll (only then) start with my normal fertilization routine.  Which is "add micros (Seachem Flourish Trace) 2x a week, according to volume" and test for individual levels of nitrogen, phoshorus, potassium & Iron (macros) and supplement as necessary, using individual products.

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On 6/11/2021 at 8:01 AM, tonyjuliano said:

Well, it's not really my "theory", most of this is based on the work of Dr. Kevin Novak.  He's had a lot of success setting anoxic filtration in ponds and the sumps of larger aquariums using baskets filled with clay and an iron source.

I'm just trying to test it at a smaller scale (much), using a method he described recently (slow-flow UGF with clay/iron source).

His work has been met with a lot of controversy and resistance, as it flies in the face of accepted dogma from the "uber planted tank" crowd, but I think his science is sound so I wanted to test for myself.  I have a background in wastewater management, and all this makes perfect sense to me.  He thinks, and I largely agree, that too many people in this hobby are raising and tending plants primarily, with little in the way of fish life. 

As far as oxygenation, the water column will continue to be oxygenated (you couldn't have any fish if it wasn't!), but the area under the plate SHOULD be severely oxygen deprived ("should" being the hopeful word, here), by lack of flow and some mysterious interaction of the clay/iron.

Hi. I like this try it and see approach. I will preface my remarks by saying I am a science nerd in real life (bio bench scientist) so feel free to answer my questions on whatever level you are working from, I will (hopefully!) follow. I don't believe in controversy where empirical data is concerned. 🙂 If it seems wrong but works then we just don't understand well enough yet.

I suspect scale may be a problem, and as @ARMYVET points out flow will be a huge key to resolving the scale issue.

Larger bodies of water stratify, and that contributes to the anoxic layer. It seems to me you almost can't have ANY flow in a 10 gallon if you want to maintain that stratification. The convection currents created in the water column by your light source might be more than enough, and you could maybe even harness that by replacing your short tube with a black colored lifter tube that is longer, and delete the airline. In a 10 gallon you could do a straight walsted and have a sucessful nonfiltered tank. A sponge filter is more than enough alone, also. So (here is the science question) how will you gauge the anoxic condition of the UGF, and how will you determine its contribution to water quality? What will be your metric of success? 

On 6/11/2021 at 8:35 AM, tonyjuliano said:

...After normal cycle is established, my nitrates should start to climb beyond what they can consume (this is where I will see if the whole "anoxic theory" can work.

If "nirvana" is achieved, and all excess nitrates are consumed by something other than plant matter...

How will you rule out that "something other than plant matter" is not simply algae? Will you black out the tanks or something? I am pretty sure my 12 chili rasboras, 30-odd shrimp and 2 pea puffers do not create enough bioload in a 7 gallon to even overwhelm one anubis, let alone a mop of java moss--my tank is plant crammed to provide cover and sight breaks, so I do need to fertilize, but if it wasn't for needing to clean up the snail carcasses (which I could just net out but siphoning is so much more fun) I would never need to change water for the fish, ever. In fact if I don't fertilize, I just get an algae bloom, but still no nitrates.

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As I think of this more...I am still intrigued... @Brandy I am wondering if the only way to truly test the activity and effectiveness of the UGF as an anoxic denitrator would be to remove from the tank anything that would contribute to the removal of nitrates....eg...the plants. 

 

Of course that is purely just for scientific data for sure and wound not be fun to look at especially if you go to the lengths of making sure not even algae is growing which also serves as a nitrate sponge.  

But the idea does have sound theories behind it as I did a bunch of reading in waste water filtration and they use plants and anoxic filtration to treat water.  

I will be watching for the updates and it will be interesting to see the results no matter what they are. I applaud @tonyjulianofor having an idea and instead of just reading or having people tell him it wont  or will work he is testing his theory.  I have always learned as much from my failures, sometimes even more than when I have succeeded.

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On 6/11/2021 at 1:42 PM, Brandy said:

If it seems wrong but works then we just don't understand well enough yet.

@Brandy That's an excellent statement, everyone should strive to adopt this mid-set.

On 6/11/2021 at 1:42 PM, Brandy said:

I suspect scale may be a problem, and as @ARMYVET points out flow will be a huge key to resolving the scale issue.

Agreed.  And if it turns out that this scalability issue is impossible to overcome, i have a backup plan.  There is an empty 24 gallon cube sitting at the ready to take this project over.

On 6/11/2021 at 1:42 PM, Brandy said:

In a 10 gallon you could do a straight walsted and have a sucessful nonfiltered tank.

This is true, and actually one of the things that lead me to this point.  I have built several Walstadt tanks, and they have been wildly successful.  I have a 20 gallon long Walstadt that has NEVER needed a water change (almost a year now!).  This is despite the fact that is has a relatively high bio-load (12 White Cloud's, 8 Cherry Barbs, 2 Dwarf Gourami's, 4 snails and many shrimp). 

I have lots of respect for Dianne Walstadt, but I also think she may have misinterpreted her own results. 

She credits the self-sustaining nature of her method to successful plant growth, supported by a natural, nutrient rich substrate and careful (plus innovative - Siesta!) light management.  What I think she may have overlooked is the fact that her methods create a natural anoxic system. 

I stumbled onto this hypothesis while marvelling at the success of my particular setup. I noticed frequent releases of "bubbles" that emanated from the substrate, and at first assumed it was sulfur dioxide being released from the natural decomposition process.  Well, I filled some shot glasses with tank water and inverted them, placing them around on the tank floor.  Finally, I caught one of those bubbles.  Guess what?  It was NOT sulfur as I thought, but instead turned out to be almost pure nitrogen gas!  The only explanation for this is that anaerobic bacteria were at work below.  I've never seen her mention this in any of her writing, and have come to think that this is the real secret of her success.

On 6/11/2021 at 1:42 PM, Brandy said:

I am pretty sure my 12 chili rasboras, 30-odd shrimp and 2 pea puffers do not create enough bioload in a 7 gallon to even overwhelm one anubis, let alone a mop of java moss

This experiment will not rely on fish waste to produce the required ammonia - that would be too variable in nature.  Instead, I will be the ammonia source.  I will dose with ammonium chloride, as required to maintain a consistent 2 ppm ammonia level.  The addition of any "live creatures" will wait until this experiment has ended.

Algae will be eliminated with the use of glutaraldehyde.

On 6/11/2021 at 1:55 PM, ARMYVET said:

I did a bunch of reading in waste water filtration and they use plants and anoxic filtration to treat water.

Yes @ARMYVET, floating islands of Pothos above and thick layers of clay and iron below are very effective "standards" used in successful wastewater treatment.

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On 6/11/2021 at 12:13 PM, tonyjuliano said:

I noticed frequent releases of "bubbles" that emanated from the substrate, and at first assumed it was sulfur dioxide being released from the natural decomposition process.  Well, I filled some shot glasses with tank water and inverted them, placing them around on the tank floor.  Finally, I caught one of those bubbles.  Guess what?  It was NOT sulfur as I thought, but instead turned out to be almost pure nitrogen gas!  The only explanation for this is that anaerobic bacteria were at work below. 

OMG, I love this!! I have some deep beds "for plant growth" and have see this too. Having worked with H2S in a lab setting, I am WELL aware that even those tiny bubbles would be detectable to my nose if they approached any kind of purity, so I also doubted that they were sulfurous. However... this leads me to wondering what specific kind of bacteria we are actually culturing in deep beds. 

I will enjoy watching this project progress.

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You nerds have already probably seen this but Dennis Wong wrote a cool article and an even better video the effects of anoxic layers in a fish tank. His conclusion is that it isn't a bad thing as usually thought. As @tonyjulianomentioned, denitrification naturally occurs in deep soil beds, as well as the reduction of iron to make it more available to plants. Only deeply anaerobic beds will produce hydrogen sulfide gas.

In some of his tanks, Dennis is using 5-7 inches of soil and aquasoil without ill effects. Same thing seems to be happening with the super deep sand beds at Ocean Aquarium.

I like the experiment, but part of me wonders if the undergravel filter is even really necessary for denitrification or if a deep bed is enough.

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Posted (edited)
On 6/11/2021 at 4:17 PM, gjcarew said:

part of me wonders if the undergravel filter is even really necessary for denitrification or if a deep bed is enough.

Don't wonder, UGF definitely isn't "necessary".  But not everyone has the "real estate" available for  5-7 inches of substrate.

The UGF concept is just hoped to be a means to accomplish this when deep beds are not feasible.

Edited by tonyjuliano
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Posted (edited)

@ARMYVET, @Brandy!!

Hot damn! Have a good look at this!

IMG_0593.jpeg.db2a2ab7b9a809d461ad53eda857ec47.jpeg

See this?  I know it looks like "whitish specks" in the photo (damn iphone can't focus close enough), but those there - they is bubbles! 

NITROGEN BUBBLES!!

Being generated at the very bottom of the tank, in an anoxic zone under the UGF plate.

I'd bet my house that this is going to work.  Methinks Dr. Novak is right!

This will all have to be verified over time, of course, but it's an extremely positive sign.

 

The other tank (which I just finished setting up this morning) - same condition!!

IMG_0594.jpeg.8722074c3419b6ca6799706d2e7e1f68.jpeg

Edited by tonyjuliano
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@tonyjuliano I love your enthusiasm but I am literally going to burst your bubble.   There is no way in hell you created an anoxic zone that fast.  You said tank 2 was just set up today ….the bubbles you are seeing are trapped air from the substrate when you started to fill the tank.  The reason I can say this with absolute certainty is I just set up a tank tonight and there are the same bubbles in the substrate.  
I believe that to create an anoxic situation takes time it would never happen that fast. I am thinking on the order of weeks minimum if not months. 
 

The pic I submitted is of a tank I set up 2 hours ago. The same White dots and my substrate is only about 2 inches deep. 46F3F8E9-AA92-4276-A3E8-ED29B8493BB7.jpeg.9663bb3af8e7c765e46236f3e4909e89.jpeg

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