Nitrate Dosing?

[IrvineHimself]

Nitrate Dosing?

In a recent thread on commissioning the Fzone CO2 generator, @Wookii brought up the subject of aquatic plant fertilisers. As I pointed out then, this is a subject for which I have a number of questions that are best answered in a separate thread.

Current Plants, Livestock and Concept:
For many years, I have had this haunting vision [almost a memory] of a dark and mysterious; moss laden aquascape with a solitary Betta slowly appearing from the gloom. While I say 'solitary Betta', I should point out that my goal is that no matter how many times you look at the 'finished tank', there will always be something new in the way of plant & livestock to be discovered.

I started planning the aquascape back in January of this year and received physical possession of my chosen tank at the end of April. At which point I spent the next month using neoprene and cardboard cut-outs to model the layout. It is a hybrid peninsular design with a front or public view and a back or private view. The hardscape forms a network of caves which run the length of the tank, and I want to grow walls of Christmas and Weeping Moss at each end of this reef with a Weeping Moss liana dissecting it. This gives me five areas of habitat [six counting floaters] with a sixth/seventh [newly liberated] area formerly occupied by my heater. (The Christmas moss wall will partially cover this latter area.)

Public view of tank


Private view of tank


Floaters


The aim is for the filter I/O wall, to have table like nodules of Christmas Moss and the outer wall to have similar nodules of Weeping Moss. The reef like structure bisecting the tank is also seeded with Christmas Moss, whereas the para-cord liana bisecting the tank at an angle is seeded with Weeping Moss.

The other plants I currently have are:

• Red Root Floaters
• Water Lettuce Floaters
• Dwarf hair grass (new)
• Pygmy Bucephalandra
• Bucephalandra
• Stem Plants (typical starter selection)
• Lobellia
• Two varieties Anubis remain (I lost another last week)

I have a long list of other plants and little tiny bits of real estate into which they will fit, but I have now lost over seven Anubis because the rhizomes turned to mush.

With regard to my floaters, as I explained to @Wookii , they have literally been put through the ringer and are in extremely poor condition. Subsequently, I noticed that a couple of leaves of Water Lettuce I got just before I got the Red Root Floaters had survived the commissioning of my new filter in a much better state than the latter. The truth is that the surface agitation with my new powerful filter is too much for floaters. I have made a couple of neoprene booms that allow good surface agitation, but contain the floaters in a calm pond. If it works, I would like to try and add a pond of Frogbit.

Anyway, on my next shopping list I have:

• More Pygmy Bucephalandra to plant along the gravel bed which will [hopefully] soon to be shaded by tables of Christmas Moss
• Four or five more of the larger Bucephalandra to plant along the reef and hardscape forming the border of the gravel bed. The aim is to create a thick jungle like barrier between the separate habitats.
• Something similar to Lobellia
• Possibly a Banana Plant or Red Tiger Lily, maybe even both.
• Frogbit?

In terms of livestock I have:

• Rock Gobies (3 but want 6)
• Kuhlis (4)
• Zebra loaches (4 but want 8)
• Pygmy Corys (5 but want 9)
• Neocaridina (want to replace with Ghost Shrimp)
• Rabbit snail (1)
• Bladder snails (not as many as I first feared)
• Endlers (10, intend to move to an overflow tank)
• X-ray Tetras (5, also intend to move to an overflow tank)

I would also like to get small oddballs like Thai Micro Crabs and other very small, weird live stock that are difficult to see. but provoke amazement when spotted. Similarly, I am constantly looking for both small and large unusual plants.

My Tank:
It is a 90 litre (60*40*40cm) tank with a Filtosmart Thermo 200 filter. I am injecting CO2 and currently dose with 'TNC Light', which contains potassium and magnesium but no iron (1% K, 0.4% Mg, 0.08% Fe, 0.018% Mn, 0.002% Cu, 0.01% B, 0.01% Zn, 0.001% Mo)

So far, I have not yet dosed with nitrates, but on @Wookii s' suggestion I have added 'TNC Complete' to my next shopping list. Also, I invested in a 'No Spill' water change system which, with my advancing years and mobility issues, makes changing water a breeze. In addition, the system means that water changes are minimally disruptive to both plants and livestock. In other words, I am fully set up to do daily water changes if necessary.

However, during all my planning, I got caught up in the current fashion of balancing livestock with nitrate absorbing plants to minimise water changes. As a result, aesthetically, I would find it very pleasing if I could find the sweet spot where the waste from the livestock provide the plants with the required nitrates.

My Dosing Questions:
Noting my primary plants are the Christmas and Weeping Moss,:

• What kind of level of nitrates should I be looking for? (As a noob, I have four test kits: Seachem nitrates, Aquarium Lab, API test strips, and JBL test strips. They all agree that with the new filter, my nitrate levels are hovering between 10 and 15 mg/l.)
• What is the best balance of nitrates between the livestocks' desire for zero nitrates and the plants nutritional requirements?
• Should I be thinking of putting grow tabs in the substrate?
• With time, patience, good observation and careful selection of plants, will it be possible to find the sweet spot where the bio-load provides all the required nitrates?

Thanks in advance for your valuable opinions.
Irvine

 

[dw1305]

Hi all,

What is the best balance of nitrates between the livestocks' desire for zero nitrates and the plants nutritional requirements?

This comes up quite a <"lot as a question">, but there <"isn't a single answer">.

Taken at its base level, the nitrate ion (NO3-) is <"many orders of magnitude less toxic"> than either nitrite (NO2-) or ammonia (NH3) <"https://faseb.onlinelibrary.wiley.com/doi/abs/10.1096/fasebj.31.1_supplement.lb277">

.........The Zebra(fish) Danio (Danio rerio) paper use NaNO2 and NaNO3 as its source of NO2-/NO3- ions. If you convert the 606 mg/L (ppm) NaNO3 to ppm NO3- you get 442 ppm NO3- (RMM 85 and 62/85 ~ 73% NO3), so we are still talking pretty elevated levels of NO3-..........

While <"every nitrate ion is the same">, their <"route into tank water can differ">, and that is <"really the important bit">.

With time, patience, good observation and careful selection of plants, will it be possible to find the sweet spot where the bio-load provides all the required nitrates?

Possibly, but probably not. That was the rationale for the <"Duckweed Index">, a floating plant would act as both nutrient sponge and nutrient test kit. You don't add nutrients until your "Duckweed" tells you to.

cheers Darrel

 

[dw1305]

Hi all,

What kind of level of nitrates should I be looking for? (As a noob, I have four test kits: Seachem nitrates, Aquarium Lab, API test strips, and JBL test strips. They all agree that with the new filter, my nitrate levels are hovering between 10 and 15 mg/l.)

If we assume that your <"test kits are accurate"> (and that is <"quite a large assumption">) I'd say that is in the <"sweet spot">.

It was actually the <"difficulties in testing for nitrate"> that led (independently) to the development of both <"Estimative"> and <"Duckweed"> Indices.

cheers Darrel

 

[IrvineHimself]

Thanks, it will take me a while to read through these links and digest, but they seem like a good starting place.🙂

 

[LMuhlen]

I don't know if this is where you are coming from, but around here, for the longest time, aquarists were taught that ammonia turns into nitrites, which turn into nitrates, and then we do water change to keep nitrates in check for the sake of the fish.

I see it as a severe oversimplification derived from people's need to be in control of their tanks. Throughout aquarium development, people have manage to fit everything that happens into the very few parameters that we can test for. Back when we could only test pH, everything wrong in a tank was because of pH. Then we got to test NH3, NO2 and NO3, so they became the parameters that explain everything. It doesn't matter that in planted tanks we often add nitrates to the tank, some people insist that we need to do water changes because of nitrates.

Reality seems to be much more complex than what the simplified "nitrogen cycle" can explain. There is a myriad of different molecules being generated and consumed in our tanks, substances that we can't measure, that we don't know about, originating from everything alive and dead. They affect fishes, plants, microbes in unpredictable ways. They are why people say that each tank is different. And this is why we do water changes, to keep the invisible stuff from getting out of hand.

The problem with assuming that you do water changes to keep nitrates in check is that it often leads you to finding a way not to do water changes. And it is true that in many cases the water changes are a bit excessive, but that is because they are intended to control the invisible, so it is better to stay on the safe side. Most people can reduce the water changes and not face any issues, but sometimes the issues start to slowly build up, invisibly, and then you get acute or chronic problems that were avoidable.

Again, I don't know if this is where you are coming from, but fishes and low nitrates are not something to be concerned about. The typical nitrate concentrations in our tanks are pretty safe. There are possibly some other nasty stuff building up in your tank that will affect the livestock directly or indirectly, and you address them with frequent water changes, good maintenance and well oxygenated water.

Regarding the idea of having the bioload provide the required nitrates, while it could be possible, it comes with severe side effects. Fishes aren't clean ammonia factories. Fish food isn't made of lab grade nitrates and phosphates only. For every nitrate ion originating from your fishes excretes and from fish food, you get a whole baggage of all the stuff we can't see or measure. That is why, ideally, you have a maintenance routine that gets rid of all the nasties and then supplement nitrates by some degree.

 

[dw1305]

Hi all,

Throughout aquarium development, people have manage to fit everything that happens into the very few parameters that we can test for.

That is really the issue, people want <"black and white"> answers in a <"shades of grey"> world.

A real problem is that people are more willing to <"believe in a magical number"> rather than the evidence of their own eyes, and then will argue <"that wrong is right "> even when it patently isn't.

The problem with assuming that you do water changes to keep nitrates in check is that it often leads you to finding a way not to do water changes. And it is true that in many cases the water changes are a bit excessive, but that is because they are intended to control the invisible, so it is better to stay on the safe side. Most people can reduce the water changes and not face any issues, but sometimes the issues start to slowly build up, invisibly, and then you get acute or chronic problems that were avoidable.

<"Totally agreed">. I have to <"apologise to"> @Miss-Pepper for the next bit, because it was a bit of a rant, but this really is <"my manifesto">.

And that is the real issue for me, many forums and LFS are advocating methods that definitely aren't best practice and in a lot of cases actively get in the way of people being successful aquarists. I would hope that you would get better advice in Germany, Sweden or the Netherlands.

There is no money to be made by telling people that "oxygen, plants and time" are the most important factors in being a successful fish keeper. If you then tell them that

• they can use garden soil capped with sand as substrate,
• that there is no point in trying to change your water chemistry with pH buffers,
• there are no special phosphors, (unique to aquarium tubes), that promote plant growth,
• you can collect rocks, wood and dead leaves safely from the wild,
• that live food, vegetables and dead leaves are cheap and good ways to feed your fish and shrimps
• that a bespoke, very expensive filter media is, at best, irrelevantly slightly more efficient than alfagrog etc.,
• that a canister filter is fundamentally a pump in a bucket.
• that snails are a good thing in the aquarium
• that a lot of aquarium test kits aren't accurate and shouldn't be used as a basis for important decisions.
• Plants need all fourteen of the essential elements for plant growth, just in vastly differing amounts.
• That every ion is the same as every other ion in solution,
• that plants can only take up nutrients as ions and
• it makes no difference to the plant if the source of a potassium ion (K+) was ADA's finest or the cheapest dry potassium salt.

Then a large amount of the products sold by the industry becomes superfluous. Some of this is my "day job", but there is a vast resource of peer validated, open source, scientific research available to every-one.

The headline news is:

• Oxygen is much more important than ammonia in "cycling".
• Nitrification is carried out by a large range of organisms that we've only discovered recently,
• and that the bacteria we thought were essential for cycling don't actually occur in aquarium filters
• If you have plenty of plants (and some with the aerial advantage) you can use them both to improve water quality and as an indication of when to add fertilisers.
• "Plant/microbe biofiltration" is much more efficient than "microbe only" biofiltration.
• Plant roots are leaky structures, leaking oxygen, nutrients and carbon into the "rhizosphere", the zone around the root, altering the microbial assemblage to the plants advantage.

Diana Walstad had to publish her book <"The Ecology of Planted Aquarium"> privately despite the fact that it was meticulously researched and full of information that the subsequent two decades has very largely validated. There were some things that she <"subsequently revised in the light of her experience">, because she is a scientist she was happy to do this.

Dr Tim Hovanec sells a product designed to help cycle aquariums, but again was happy to revise his products and advice in light of scientific advances, but then you go onto to a forum and you read the same old, totally discredited, advice repeated time after time, and it really p*sses me off, because it is one of the things that is standing in the way of people having healthy vibrant aquariums that they can enjoy, rather than staggering from disaster to disaster.

cheers Darrel

 

[_Maq_]

@dw1305 , ... if only you didn't mention Diana Walstad I'd fully subscribe to your manifesto, Darrel.

 

[dw1305]

Hi all,

....... if only you didn't mention Diana Walstad I'd fully subscribe to your manifesto

Next time I have a real rant I'll leave her out.

cheers Darrel

 

[tam]

Off topic ish... but Anubias is pretty tough. There is a 'disease' refered to as 'anubias rot' or similar but I'm not sure if it's been confirmed as an actual disease or it's just symptoms of an unhealthy plants. If you notice the rhzome starting to rot, cut it cleanly above the effected area.

I'd be inclined to avoid more anubias until you've had a few months without issue if you've lost a few plants. You might like to look at Schismatoglottis prietoil - it's small and sort of a cross between anubias/buce in habit/looks with crinkle edge bright green leaves.