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Cycling - Soft acidic water

Joelhill84

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Hi guys,

This is my first post here, I’m relatively new to the hobby, I’ve had a 30 liter nano tank with shrimp in the past. I’m trying to do a fishless cycle. I added 2ppm ammonia 7 days ago and it hasn’t gone down yet, after some research I think I worked out why..

My tap water parameters are:

pH: 6.6
KH and GH both less than 1

Tank parameters:

pH: less than 6
KH: less than 1
GH: 2

I’ve read that such a low pH can stall a cycle and stop the bacteria from forming.

I can’t test the ph actual reading in my tank because I don’t have a low range test kit and couldn’t find one in store.

I am running co2 which I’ve read can lower the pH by 1 point, I also have a piece of driftwood, corbo root, dragon stone and slate in the tank.

I noticed that the co2 drop checker also does not change back to blue when co2 is off, but read that the drop checker fluid is essentially pH water, could this be affected by it being such a low pH?

My main question is how can I cycle my tank? The pH is very low from tap water, I’ve read that I can add crushed coral to my filter, I have an Oase bio master 350, and this will raise the pH to allow a cycle, but once it has cycled and pH drops again, will the bacteria still be there or die off again? I only plan to keep some snails, neocaridina and possibly chilli rasboras in the future

My apologies for such a long post but I’m struggling to find definitive information elsewhere online.

Thank you
 
Thanks Darrel

I have a bag of crushed coral that I can add to the filter longer term.

I’ll see how I get on with the cycle whilst increasing Dkh using equilibrium

My plant order is due on the 15th so hoping it will be sorted for then


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Hi all,
I have a bag of crushed coral that I can add to the filter longer term.
That will do.
I’ll see how I get on with the cycle whilst increasing Dkh using equilibrium
SeaChem Equilibrium contains potassium (K), calcium (Ca), magnesium (Mg) and sulphate (SO2), so there isn't anything wrong with it, other than the price.

Cheers Darrel
 
I’ll see how I get on with the cycle whilst increasing Dkh using equilibrium

I'm no Chemist and never used Equilibrium, but looking below I understand that it will not raise the KH significantly if at all, on it's own. If you want to stick with Seachem you will need to spend more money.
Quote: 'Equilibrium™ raises the essential mineral/electrolyte content (General Hardness) of the water to balance with and promote stability of the carbonate hardness. To maintain KH, we recommend Alkaline Buffer™'.
I also think worrying about KH is a bit of a moot point when using active substrates, at least for the first 6 months or so anyway.

Copied from their website.

Soluble Potash (K2O)23.0%
Calcium (Ca)8.06%
Magnesium (Mg)2.41%
Iron (Fe)0.11%
Manganese (Mn)0.06%

[th]
Guaranteed Analysis
Amounts per 1 g

[/th]

Elemental potassium is present at a concentration of 195,000 ppm (19.5%). Fertilizer laws require us to list potassium in terms of equivalence to a material that is not present (K2O) rather than the more scientifically sound method of simple elemental equivalence.
Derived from: potassium sulfate, calcium sulfate, magnesium sulfate, ferric sulfate, manganese sulfate.

Cheers!
 
Hi all,
..... but looking below I understand that it will not raise the KH significantly if at all, on it's own
It won't.
'Equilibrium™ raises the essential mineral/electrolyte content (General Hardness) of the water to balance with and promote stability of the carbonate hardness.
It is back to SeaChem's <"way with words">, their, very carefully written, advertising spiel which implies something, without ever actually stating an untruth.
To maintain KH, we recommend Alkaline Buffer™'.
That also gets a mention <"Who needs a tank for a dark start…. Let’s see.">.
I also think worrying about KH is a bit of a moot point when using active substrates, at least for the first 6 months or so anyway.
Agreed, they are going to reduce dGH and dKH, by swapping a <"proton (H+ ion) bound on the substrate"> with a cation of higher valency (like calcium (Ca++)) in the water column. Acids are "proton donors" <"Theories of acids and bases"> and the addition of a proton will convert some of the carbonate buffer (dKH) from HCO3- to CO2.
The Bronsted-Lowry Theory of acids and bases
The theory
An acid is a proton (hydrogen ion) donor.
A base is a proton (hydrogen ion) acceptor.
Copied from their website.

Soluble Potash (K2O)23.0%
Calcium (Ca)8.06%
Magnesium (Mg)2.41%
Iron (Fe)0.11%
Manganese (Mn)0.06%
It is a polysulphate fertiliser re-labelled and sold at an immense mark-up <"Introducing a New Multi-Nutrient Fertilizer – Polysulphate">.
As an example we are suspect that Seachem buy a <"polysulphate fertiliser">, and just re-packet, and re-brand, it as <"Seachem Equilibrium"> - <"Polysulphate - Origin Fertilisers">.
The reason it has the potassium (K) in it, which doesn't contribute to the dGH, isn't because Seaxhem have added it, it was in the original product that they they have "re-imagined" as <"Seachem Equilibrium">.
Polyhalite is a single crystal complex and it is not a mixture of sulfates. The chemical formula is: K2Ca2Mg(SO4)4•2(H2O).

Unlike blended or compound fertilizer, Polysulphate is available in its natural state. It is mined, crushed, screened and bagged, all involving no chemical separation or other industrial processes. As a result Polysulphate has a low carbon footprint and is very suitable for growers using low CO2 production practices.

cheers Darrel
 
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I dosed tank with Equilibrium and Alkaline buffer yesterday, and got a nitrite reading of 0.25 last night.
This morning, I tested, had an ammonia reading, but no nitrite. I was expecting to have a nitrite reading still, given that I still have ammonia.

I have changed 75% of the water and dosed with Equilibrium and buffer again. Will see I how can get on.

Do you think there is another missing part of the puzzle here? I would prefer not to be chasing parameters once the fish and plants are in.

I am hoping that the 50% water change once a week will be enough to keep the bacteria happy.
 
Hi all,
I dosed tank with Equilibrium and Alkaline buffer yesterday, and got a nitrite reading of 0.25 last night.
This morning, I tested, had an ammonia reading, but no nitrite. I was expecting to have a nitrite reading still, given that I still have ammonia.
There are a number of possibilities. One is that you have COMAMMOX Nitrospira present, which convert ammonia straight to nitrate (NO3-) without producing any nitrite (NO2-). It looks like COMAMMOX Nitrospira are common in aquarium filters (in fact they look to be ubiquitous in all situations with low ammonia loading). There is some discussion of this in: <"Correspondence with the Neufeld lab. University of Waterloo"> - <"Comammox Nitrospira among dominant ammonia oxidizers within aquarium biofilter microbial communities - PubMed"> & <"Comammox Nitrospira Dominates the Nitrifying Bacterial Community in the External Canister Biofilter in the Tank Fish Farm">*.

You may also have non-COMAMMOX Nitrospira present converting NO2- to NO3-, Tim Hovanec talks about this in <"Dr Timothy Hovanec's comments about Bacterial supplements">.

The other possibility is that your test kit isn't actually measuring NO2-, or NH3, accurately and these results are "noise", rather then actual readings.

*I'll start a new thread for this one.

cheers Darrel
 
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Interesting, within 3 hours of changing water, I have .5ppm of Nitrate. Not convinced it is related to hardness or ph.

Suspect something else is limited for the bacteria, and I am adding it with the water change. Could be oxygen for example. I don't have any plants in the tank. The filter is creating surface agitation, but perhaps not enough.
 
Hi all,
Suspect something else is limited for the bacteria, and I am adding it with the water change. Could be oxygen for example. I don't have any plants in the tank.
That is a distinct possibility, and one of the reasons why I've gone away from attempting empirical measurement of some parameters.

There is a more complete discussion in <"Testing and What to Test">, but it was difficulties in accurately measuring nitrate (NO3-) levels that led, independently, to both <"Duckweed"> and Estimative Indices (EI).

In reality I just approached this question from a different angle, the problem is just one of designing systems ("aquariums") which ensure that <"high levels of dissolved oxygen"> were always present and plants are <"the gift that keeps giving"> in oxygen terms.

cheers Darrel
 
This is puzzling me now.

Checked nitrites again at 6pm - expecting it to have increased - it was 0ppm again.

The water was back to zero gh and kh. There is still ammonia present, coming from the aqua soil

Have dosed it up and will see what it’s like later.

Im worried about how I’m going to maintain bacteria in this tank when I start adding fish.


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You honestly don't need to worry.
This. Really, truly.

Don't change your water parameters for bacteria's sake. Leave your parameters where you want them to be long term and let the environment select for the appropriate nitrifying microbes. Nature isn't going to let yummy nitrogen species float around in the water unbothered. This is like throwing an apple in the forest and worrying it's going to sit there uneaten forever. This is a "life finds a way" and a "if you build it, they will come" situation with regards to nitrification. Once your plants are growing you will look back and wonder why you were so concerned about this.
 
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This. Really, truly.

Don't change your water parameters for bacteria's sake. Leave your parameters where you want them to be long term and let the environment select for the appropriate nitrifying microbes. Nature isn't going to let yummy nitrogen species float around in the water unbothered. This is like throwing an apple in the forest and worrying it's going to sit there uneaten forever. This is a "life finds a way" and a "if you build it, they will come" situation with regards to nitrification. Once your plants are growing you will look back and wonder why you were so concerned about this.

Great post! This should be added to every cycling query thread!

Totally agree, bacteria and their kin haven’t mastered 3.5 billion years of this planets evolution to be worried about a few missing salts, or indeed anything else.


I think I’ll just have to hope substrate stops leeching quite as much ammonia before my plants come

Just keep up with frequent water changes, add the plants when you have them, make sure you feed them, and relax and enjoy.
 
Thanks all,

I feel a lot more confident with all of your answers now. I’m doing 50% water changes each day to rid of the ammonia that I put in and just letting plants grow. I’ll wait until I want to add livestock but with my tap water caridina look a lot better so I’ll look at buffering the GH when it get closer to wanting to add them
 
Thanks all,

I feel a lot more confident with all of your answers now. I’m doing 50% water changes each day to rid of the ammonia that I put in and just letting plants grow. I’ll wait until I want to add livestock but with my tap water caridina look a lot better so I’ll look at buffering the GH when it get closer to wanting to add them

Sounds sensible. I am going to do the same 🙂

Good luck


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This cycle is mystifying me.

No nitrites today. Gh and Kh are above zero.

One hypothesis - the ammonia I am reading is ammonium. On this basis, I added some ammonia to see if any nitrite appeared - nope.

Next hypothesis - not enough oxygen (water changes would add lots and explain why I get a nitrite reading a few hours after change).

I have added an air pump, so let’s see if I have a reading tomorrow.

If that doesn’t do it - I’m stumped!

Any other thoughts on what might be limiting bacterial activity, which is temporarily resolved by a water change?

I just need to see a zero ammonia reading before I can start stocking and planting


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You can plant before hand. Infact, it will help cycle/mature the tank, so my advice is get your plants in.
The plants will be getting planted on Saturday next week regardless - as I have a huge plant order being delivered on Friday 🙂

I was hoping to get the ammonia leeching from the substrate under control by then to minimise melting and daily water changes.
 
Hi all,
You can plant before hand. Infact, it will help cycle/mature the tank, so my advice is get your plants in.
That one.
I was hoping to get the ammonia leeching from the substrate under control by then
That is an advantage of a floating plant, they have<"access to atmospheric CO2">, this means that <"they aren't carbon limited"> and <"can utilise ammonia etc"> more fully.
One hypothesis - the ammonia I am reading is ammonium.
All <"the test kits"> work by converting all the <"Total Ammoniacal Nitrogen (TAN)"> to either ammonium NH4+, or ammonia (NH3). They do this by altering the pH, because at very low pH values all the TAN is ionized (NH4+) and at high pH values all unionized and NH3.

Percent-abundance-of-ammonia-and-ammonium-across-a-range-of-pH-values-in-a-closed.png

Very odd. Airstone in the tank for 14 hours and no nitrites or reduction in ammonia ........... If that doesn’t do it - I’m stumped!
I still think that it maybe the test kit: <"ADA 60F iwagumi">.
Any other thoughts on what might be limiting bacterial activity, which is temporarily resolved by a water change?
Honestly I would just stop worrying about it. Plant the tank, change some water <"and wait">, once the plants have grown in you can add some livestock, it really is as simple as that.

cheers Darrel
 
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