[Flear]

if there is a more appropriate place for this thread, please advise and move
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how many people here are interested in the idea of a self-sustaining aquarium ?

those that have thought about it, but not tried. ?
those that have tried, maybe it failed, (what was learned) ?
those that have curiosities that may need to be considered at addressing such an idea. ?

-first, looking for other minds with similar interests, or those who have learned a thing or two from the attempt

 

[rpadgett37]

if there is a more appropriate place for this thread, please advise and move
---

how many people here are interested in the idea of a self-sustaining aquarium ?

those that have thought about it, but not tried. ?
those that have tried, maybe it failed, (what was learned) ?
those that have curiosities that may need to be considered at addressing such an idea. ?

-first, looking for other minds with similar interests, or those who have learned a thing or two from the attempt

I have an interest in this area myself. I can't say that I understand how plants fit into the nitrogen cycle very well, but I will have a tank set up in the next couple of weeks that will use plants exclusively as the filtration system.

It is a small BW aquarium with a very low PH that I am stocking with tiny nano fish. As I understand how these work, you can't grow out nitrifying bacteria because of the low PH, so you have to use plants.

I'll be using Hornwort, planted wisteria, frogbit and duck weed as the plants. All fast growing, with the nutrient hog Hornwort as the center piece. This will be my first attempt at something like this.

 

[Flear]

will read more later when i have more time

plants can either take in ammonium directly (if your pH is low) or they will take in nitrates (costs the plants more energy to process as they run nitrates backwards through the cycle till they have ammonium

ammonia is not the same as ammonium here

as the plants will suck back nitrates, this is removed from the equation of any reason for water changes, nitrates will not build up, ... unless you are overstocked and/or don't have enough plants to handle the amount of nitrates being produced in your tank

 

[Flear]

low pH screws up the nitrogen cycle

all potential ammonia is converted to ammonium
ammonium in non-toxic to fish, ... not low, but non-toxic, ... you could have lots of ammonium and still be fine

a low pH being under 6.5.

plants can absorb directly ammonium and use it, and are very happy to do so

test kits don't test ammonium, only ammonia, so how much you have in your tank becomes a mystery, ... and the plants are just happy it's there.

---

word of warning, ... if your pH shifts though, ... say it reaches 6.8, ... all your fish die due to ammonia spike.

 

[Mikaila31]

Most test kits do actually test for ammonia/ammonium. The most common one in this hobby - API 'ammonia' test does test for both. This is considered a total ammonia test (NH3/NH4+). You can get tests that just test for free ammonia which is just NH3.

Self sustaining is not possible since a natural ecosystem itsn't self actually self sustaining either. There are a massive number or reason it would not work long term. Also attempting it would severely limit what you can do and keep.

 

[Flear]

it tests for ammonia, requires you to know your pH, then you look through the chart to see remaining ammonium

wait, that's nutrafin, ... well that's how that one works

 

[rpadgett37]

I must apologize as I jumped into this thread a little too quickly.

My knowledge at this point is pretty much limited to the front end of setting up and cycling the aquarium. What is lacking for me is knowledge of how to sustain the aquarium. By that I don't mean the usual maintenance and water change tasks. I mean the care and maintenance of the eco-system... plants, nutrients, and so forth. I understand very little of what give and take is happening among the plants, bacteria and fish that inhabit the aquarium, and what role I play in encouraging and maintaining that balance. Also in terms of what tools do I use while fulfilling the role of care taker.

My tank I described above is the first where I will have to use plants alone for the filtration. I am very interested in how to help that along so it works well. That is far from creating a self-sustaining environment, which I am quite certain is beyond my grasp right now.

I am going to follow this thread, though, as I am certain to learn a thing or two as it unfolds.

 

[Mikaila31]

it tests for ammonia, requires you to know your pH, then you look through the chart to see remaining ammonium

wait, that's nutrafin, ... well that's how that one works

APIs test is for total ammonia - both NH3 and NH4 are reported on that test. It does not differentiate between them. Total ammonia is the idea ammonia test to use since NH3 and NH4 don't really matter apart from they should not be in a stable tank. If you add prime or something its going to lock all ammonia as ammonium for 1-2 days so again regardless. You want to know total ammonia since even the mostly non-toxic ammonium should not be present in a stable aquarium. Ammonium is a precursor to nitrite same as ammonia, if the biofilter gets ammonium it will still produce nitrite. Thus we care most about total ammonia not free ammonia.

 

[corina savin]

If there is no bacteria, then there is no nitrate.
A pH 6.5 is not low enough to slow down the bacteria.
Even if your test show zero ammonia/ammonium, zero nitrite and zero nitrate, you'll still have to do water changes. Plants will need minerals (over time, they will deplete). Also, fish release pheromones into the water. Pheromones accumulate over time, signaling "crowding". Fish stop growing.
Water evaporates, needs replaced, unless it rains. pH keeps dropping because of organic acids. Some fish can go as low as 3.
Too many things to think about...

 

[Flear]

plants can be used alone to ensure nitrates are at acceptable levels, ... if you have lots of plants and/or low bioload.

some fish this alone will provide all that's necessary that you don't have to change the water.
other fish this is a recipe for heartbreak to come home to dead fish.

different fertilizer styles change things.
some fertilizers are based on ensuring nothing gets to low,
some fertilizers are based on the idea of providing lots, ... possibly more than your plants could use, and so you must preform water changes to prevent things from building up to toxic levels

after this, i don't have clear reasons for or against regular maintenance as any reason could be contradicted by the next.

if i do regular maintenance on my one tank i won't learn what could go wrong, it won't inspire me to seek answers because i will never know what is going wrong to know what to search for

this also has drawn some criticism,

 

[Flear]

corina, organic acids may drop pH
dissolved minerals raise pH also

 

[Mikaila31]

some fish this alone will provide all that's necessary that you don't have to change the water.

Not sure why you still believe this. But no. Some fish may Survive longer then others but thats not meaning necessary or non-necessary.

 

[Flear]

mikaila, good clarification.

 

[Flear]

Substrate

is it possible to solve issues between anoxic zones in the substrate and roots adding O2 to the substrate ?

a DSB allows for Anoxic substrate.
needed for processing nutrient cycles
-i don't have a full list of each nutrient, but enough to know without any anoxic area, various nutrients will build up in forms nothing can use.

roots add oxygen into the substrate (for the health of the root)

are plant roots an enemy in this ?, or is there anything that can be done that would ensure that over time there will be anoxic areas that will remain to finish cycling these nutrients ?

 

[jaysee]

if i do regular maintenance on my one tank i won't learn what could go wrong, it won't inspire me to seek answers because i will never know what is going wrong to know what to search for

As the saying goes - when everything you've done is wrong, what's left is what's right. Certainly there is more to learn from failures than there is from success. Anyone can simply follow instructions and succeed - doesn't mean that they understand why it is they do the things they do, or more so, the "risks" associated with deviation from the instructions. I mean, I can follow instructions and bake a cake time and time again. And then a cake comes out messed up - not that I have any idea why, cause all I've ever done is follow instructions to success. Now had I not enjoyed immediate success through directions, I would have more failures under my belt - enough to be able to deduce that I used too much flour or whatever.

Too, anyone who is not willing to risk "failure" is not going to learn much about capacities and limitations.

 

[Flear]

jaysee, ... thank you

now if i more of a mind for scientific process ...

process is so painfully slow at times
at times i just go with what i feel, which gives more inspiration into ideas that i think i would ever have otherwise

 

[Mikaila31]

You would need to make the substrate deep enough that plants would not root all the way down, or have significantly large unplanted areas to try and encourage anoxic zones but that wouldn't be a guaranty especially with heavily rooting plants. Also minimal to no current. Then you have to realize these conditions will have on more then just anoxic zones.

You are still lingering on nutrient cycling and redox which is again just the beginning of how an ecosystem operates. You fix the anoxic issue then there will be another issue and so fourth and so on. Issues that will have nothing to do with nutrient cycling and all about biological stability and viability.

Mulm build up and nutrients falling out of cycle is natural. Cycles are not indefinite, nutrients are always being added or removed to the system both organically and inorganically. You can keep asking and looking for ways around this but it is what it is. There is no current magic that lets you break physics yet and give you something for nothing.

I am all about pushing limitations and currently do and have for many years. The more natural you want to go the more the tank is going to look like it belongs in a swamp. Then when you get to the point where you don't even want to stick your siphon in there let alone your hand, you will then question why you bother pushing such limitations. Sure fish seem happy, plants look like crap from build up of mulm, any optional powerhead is probably clogged by mulm now too regardless of it if has any 'filtering' abilities. By then you have seen so many population explosions of things you have no clue of so you just let them be and wait for them to crash before touching the tank any further. I have lots of pictures of lots of things you generally don't want your tank to look much like both from the past and the present.

So yeah just change water, its much easier and rewarding IMO. You can do anything along with, soil substrates, non-filtered, ect and still be good.

 

[Flear]

Mikaila

you have no idea how thankful i am of your advice
i'm thankful i'm stubborn, or i would have given up

the redox and nutrient thing may be the basics, ... have to start somewhere (i'm guessing 5"), ... yes, it's got issues that i can't imagine how to overcome, aside from floating plants, not quite what i would prefer, ... and floating plants are only floating till their roots find ground, then they become anchored

ya, that's an area i don't have a fix or idea for.

 

[jaysee]

Honestly, I think it would be an eyesore to have 5 inches of substrate in the tank.

 

[Mikaila31]

some plants are strict floating plants, other are considered rootless. Duckweed, dwarf water lettuce, hornwort, then the mosses are not considered rooting plants, roots primarily provide attachment are and very short.Anchored is diff then rooted. Most all stem plants have minimal roots that primarily anchor.

On the other hand an amazon swords roots can easily cover a 2x2' area.

Far as pore size I would say smaller, many plants root better in fine gravel then sand... but not always. Fine gravel to straight up topsoil my tanks still get good root development against the bottom glass with 3" of substrate.