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Dax21

Aquarium Advice Newbie
Joined
May 14, 2023
Messages
7
Hello everyone,

I hope this message finds you well.

I need some little advice in regards my tank parameters.

I have a 125L tank with 5x juvenile Discus, 2x Angelfish and 3x Corys.

I had the tank for over a year with only 2x Angelfish and 3x Corys and 2 weeks ago I decided to purchase 5x Juvenile Discus.
Obviously this made the biological load to increase and my ammonia also increased. It fluctuates from 0.25ppm to 0.50ppm ammonia as I do 2x 25% water changes a day 1h after each meal (For the quick healthy and grow of my discus). My nitrites and nitrates are always 0ppm both. I use seachem Prime (To detoxify ammonia) and stability each water change.
I use a 307 Fluval external filter with 2x trays of Seachem matrix. Also 2 days ago a decided to add 2x Ziss ZB-200F & ZB-150F Bubble Moving Media Filter into the tank to increase the biological space.
I have also plants in my tank.

Do you know if I continue doing 2x 25% water changes daily it will managed to grow enough beneficial bacteria in the tank? I would like to have a 0ppm reading in ammonia soon.

Thank you all for your time and help.

PS: I am sorry if I have spelled any words wrong, English is not my first language.
 
Your bacteria bed will always grow to the point where it consumes all the ammonia present unless the Ph is so low that it inhibits bacterial growth. All that just takes time. Nitrifying bacteria need oxygen so anywhere in the tank where there is a higher amount of oxygen ( usually but not only in the filter) there will be nitrifying bacteria to consume the ammonia.
With that said, if your Ph is below 6.8, the ammonia is converted to ammonium which is not toxic to the fish so the use of the detoxifiers is not necessary.
There is much debate on water changes with Discus but I'm from the "The more changes the better" school of raising Discus so I would be doing the daily changes even if your ammonia is not the issue. ( This is something I learned from the late Jack Whattley. )
So how you proceed is going to be dependent on your tank water's parameters and your replacement water parameters.
 
Your fish will always be producing some ammonia throughout the day between your water changes. Even if you did a 100% water change or 10 water changes per day such that the level of ammonia was so low to be undetectable, there would still be ammonia in the tank, enough to cycle your tank. Keeping it at that 0.25 to 0.5 level will be fine.
 
Thank you for your reply and advice!

My PH is around 6.4 / 6.6 as I added some crushed coral into my external filter 8 days ago.

I was just a bit worried that making 2x daily water changes of 25% each will never balance the beneficial biological bacteria in my tank. Also not having nitrates reading was worrying me.

So should I keep going with daily routine of doing those water changes until everything balanced out? My idea is doing 1x daily water change instead of 2x.

Thank you again
 
Thank you for taking the time to answer my post.

I fully agree with you, this something that is part of this hobby!

As mentioned on my reply to Andy Sager, my worries were the reading of ammonia and none of nitrates (I have real 4x plants in my tank but there are not covering the whole tank).
 
Unless you have plants then zero nitrate is ideal. Changing water everyday will be be removing both ammonia and any nitrate that comes out of your cycle, so low to zero is expected. I wouldnt even bother testing for nitrate until your cycle has established so you can see what it settles at once your water changes are at a more normal schedule.
 
Thank you for your reply and advice!

My PH is around 6.4 / 6.6 as I added some crushed coral into my external filter 8 days ago.

I was just a bit worried that making 2x daily water changes of 25% each will never balance the beneficial biological bacteria in my tank. Also not having nitrates reading was worrying me.

So should I keep going with daily routine of doing those water changes until everything balanced out? My idea is doing 1x daily water change instead of 2x.

Thank you again

How low was the Ph before adding the crushed coral? Below 6.5 will inhibit Nitrifying bacteria growth but below 6.0 will prevent nitrification all together. If you raise the Ph above 7.0. ammonia will become a problem if it rises above the .5 ppm.
 
When I checked my ph was 6.0 (it's the minimum that my API Ph liquid could read).
8 days ago I added crushed coral to my filter to increase the Ph to my tank which 2 days after started reading between 6.4/6.8 until now and stays stable on those parameters.

The water ph reading here in the Isle of Man is around 7.0/7.2
 
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Hello, I'll let you know now I have 0 experience in keeping discus cichlids. But I thought I would give you a heads-up.
Discus cichlids are a high temperature fish(82°-86°f). 82°f is a few degrees over the max temp for most cory's & max temperature for angels.
This is one reason I've never kept & other is how sensitive to water quality they are. Hopefully this helps!!!!!
 
When I checked my ph was 6.0 (it's the minimum that my API Ph liquid could read).
8 days ago I added crushed coral to my filter to increase the Ph to my tank which 2 days after started reading between 6.4/6.8 until now and stays stable on those parameters.

The water ph reading here in the Isle of Man is around 7.0/7.2

Okay. Just keep an eye on the Ph so that if it rises above 7.0, you address the ammonia with a water change vs using a detoxifier as detoxifiers do not last more than 24-48 hours per dose.

Regarding M.J.Gomez's comment, are these wild Discus you have or domestic strain(s)? What was the temperature they were kept at where you got them? Many domestic strains do not follow natural conditions for wild caught fish. Re temps for the cories, there is a short list of varieties that will do well in " Discus" temps but many species will not fair well for long. You need to balance the temps that will keep your Discus healthy while not stressing your cories. ( There is always the option of setting up another tank for the cories with a lower temperature. ;) (y) )
 
PH will stall the nitrogen cycle if you have ammonia oxidising bacteria as your primary nitrification microbe but bacteria are NOT the primary nitrifying organism in aquarium filters.

The primary nitrifying organism for nitrification in freshwater aquarium filters are a type of Archaea which have a wider tolerance to oxygen levels and pH. Therefore nitrification is unlikely to stall at lower pH.

At the time researchers were discovering nitrification and the responsible microbes, the data was not collected from a typical aquarium filter and was extrapolated from waste water treatment. That is where the research of nitrosomonas and nitrospira bacteria came from.

Scientists have now discovered that an aquarium filter does not have these microbes in abundance and so all references to pH levels stalling these organisms and the nitrogen can now be ignored.

Whilst water changes can help dilute ammonia, they can also raise pH which and make any remaining ammonium become more toxic so be careful with water changes in this regard.

As for Discus parameters I am out of my depth so cannot offer advice.
 
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Your tank isn't big enough for discus. They can reach 10 inches in diameter and regularly hit 6 inches in diameter. The smallest size tank for a pr of discus is 4 foot long x 2 foot wide x 2 foot high. A bigger tank is required if you want more than 1pr.

Freshwater angelfish can reach 5-6 inches long and up to 8 inches high, but are usually less and regularly grow to 4 inches long x 6 inches high. They should have an aquarium that is at least 3 foot long x 18 inches high x 18 inches wide.

Corydoras need to be kept in groups of at least 6 (preferably 10) or more. They generally come from cooler water than discus (as mentioned by m.j.gomez) and don't really do well at high temperatures for a long period of time.

Discus need temperatures of 26-27C (79-81F) up to 32C (90F).
Most Corydoras need temps between 16-26C (60*79F).
Angelfish have temps between 24-28C (75-82F).

Discus need lots of plant matter in their diet and do best in well planted aquariums.

More information on discus can be found at the following link
https://moam.info/the-discus-fish-symphysodon-scielo_59c411371723ddc7f4532afc.html

--------------------

Big water changes will dilute stuff more effectively than small water changes. If you change half the water in one go, it will dilute everything in the tank water by half.

If you do a 25% water change, you leave behind 75% of the bad stuff in the water.
If you do a 50% water change, you leave behind 50% of the bad stuff in the water.
If you do a 75% water change, you leave behind 25% of the bad stuff in the water.
 
This is from a 2020 article on nitrification (https://www.tfhmagazine.com/articles/freshwater/nitrifying-bacteria) : "Indeed, in recent years studies published in academic journals have suggested that other bacteria, most notably a species known as Nitrospira, may actually be handling much of the nitrification in fish tanks. “Bottom line is this: there are a lot of species of bacteria that will feed on nitrogen compounds,” said Thom Demas, curator of fishes at the Tennessee Aquarium in Chattanooga, the world’s largest freshwater aquarium. “It’s most probable that there are many bacteria responsible for the nitrogen cycle in any given place at any given time.”

This from a 2021 Oklahoma state university fact sheet on aquaponics (https://extension.okstate.edu/fact-...tion,, Nitrococcus, Nitrospira and Nitrospina. ): "During nitrification, ammonia attracts ammonia-oxidizing bacteria Nitrosomonas, Nitrospira, Nitrosococcus, Nitrosolobus and Nitrosovibro, as well as nitrite-oxidizing bacteria Nitrobacter, Nitrococcus, Nitrospira and Nitrospina. "
And this from a 2022 article from a questionable source (https://aquariumscience.org/index.php/2-12-beneficial-bacteria/) : "There are several general types of beneficial bacteria involved in oxidizing ammonia to relatively safe nitrate in the freshwater aquarium. Scientists call these organisms “nitrifying” bacteria and archaea. We will use the term “beneficial bacteria” for both the nitrifying bacteria and the nitrifying archaea. Below in this article, we try to explain the complex science of “beneficial bacteria”.

This information is not necessary for setting up new aquariums or running existing aquariums. But some like to delve into the science. Read on if you are so inclined. Just be prepared for a very boring, long-winded dissertation only true nerds such as the author will be interested in.

Dimidiochromis compressiceps OB Malawi Eye Bitter
Dimidiochromis compressiceps OB Malawi Eye Bitter
Beneficial Bacteria in Depth
From a pure science perspective there are a whole series of “beneficial bacteria”, with more being discovered every year.

“Ammonia-oxidizing archaea and complete ammonia-oxidizing Nitrospira in water treatment systems”, Al-Ajeel 2022

“The sequential steps of this respiratory process are carried out by distinct microbial guilds, including ammonia-oxidizing bacteria (AOB) and archaea (AOA), nitrite-oxidizing bacteria (NOB), and newly discovered members of the genus Nitrospira that conduct complete ammonia oxidation (comammox). Even though all of these nitrifiers have been identified within water treatment systems, their relative contributions to nitrogen cycling are poorly understood. Although AOA contribute to nitrification in many wastewater treatment plants, they are generally outnumbered by AOB. In contrast, AOA and comammox Nitrospira typically dominate relatively low ammonia environments such as drinking water treatment, tertiary wastewater treatment systems, and aquaculture/aquarium filtration.”

So the bottom line appears to a combination of bacteria and archaea are present so Ph will effect nitrification.
 
Okay. Just keep an eye on the Ph so that if it rises above 7.0, you address the ammonia with a water change vs using a detoxifier as detoxifiers do not last more than 24-48 hours per dose.

Regarding M.J.Gomez's comment, are these wild Discus you have or domestic strain(s)? What was the temperature they were kept at where you got them? Many domestic strains do not follow natural conditions for wild caught fish. Re temps for the cories, there is a short list of varieties that will do well in " Discus" temps but many species will not fair well for long. You need to balance the temps that will keep your Discus healthy while not stressing your cories. ( There is always the option of setting up another tank for the cories with a lower temperature. ;) (y) )

Thank you Andy Sager! I will keep you update on that
 
Your tank isn't big enough for discus. They can reach 10 inches in diameter and regularly hit 6 inches in diameter. The smallest size tank for a pr of discus is 4 foot long x 2 foot wide x 2 foot high. A bigger tank is required if you want more than 1pr.

Freshwater angelfish can reach 5-6 inches long and up to 8 inches high, but are usually less and regularly grow to 4 inches long x 6 inches high. They should have an aquarium that is at least 3 foot long x 18 inches high x 18 inches wide.

Corydoras need to be kept in groups of at least 6 (preferably 10) or more. They generally come from cooler water than discus (as mentioned by m.j.gomez) and don't really do well at high temperatures for a long period of time.

Discus need temperatures of 26-27C (79-81F) up to 32C (90F).
Most Corydoras need temps between 16-26C (60*79F).
Angelfish have temps between 24-28C (75-82F).

Discus need lots of plant matter in their diet and do best in well planted aquariums.

More information on discus can be found at the following link
https://moam.info/the-discus-fish-symphysodon-scielo_59c411371723ddc7f4532afc.html

--------------------

Big water changes will dilute stuff more effectively than small water changes. If you change half the water in one go, it will dilute everything in the tank water by half.

If you do a 25% water change, you leave behind 75% of the bad stuff in the water.
If you do a 50% water change, you leave behind 50% of the bad stuff in the water.
If you do a 75% water change, you leave behind 25% of the bad stuff in the water.



Thank you for your message.

Juvenile discus requires 20L per discus. Older discus (Starting from a year old) requires a minimum of 25L per Discus. Once they reach the year old they will move to a bigger tank.
Optimal temperatures for Discus are 29-30 Degrees Celcius, 27 is too low.

The coridoras I have in my tank are able to live in the same temperatures as my discus also for the angel fish.
 
This is from a 2020 article on nitrification (https://www.tfhmagazine.com/articles/freshwater/nitrifying-bacteria) : "Indeed, in recent years studies published in academic journals have suggested that other bacteria, most notably a species known as Nitrospira, may actually be handling much of the nitrification in fish tanks. “Bottom line is this: there are a lot of species of bacteria that will feed on nitrogen compounds,” said Thom Demas, curator of fishes at the Tennessee Aquarium in Chattanooga, the world’s largest freshwater aquarium. “It’s most probable that there are many bacteria responsible for the nitrogen cycle in any given place at any given time.”

This from a 2021 Oklahoma state university fact sheet on aquaponics (https://extension.okstate.edu/fact-...tion,, Nitrococcus, Nitrospira and Nitrospina. ): "During nitrification, ammonia attracts ammonia-oxidizing bacteria Nitrosomonas, Nitrospira, Nitrosococcus, Nitrosolobus and Nitrosovibro, as well as nitrite-oxidizing bacteria Nitrobacter, Nitrococcus, Nitrospira and Nitrospina. "
And this from a 2022 article from a questionable source (https://aquariumscience.org/index.php/2-12-beneficial-bacteria/) : "There are several general types of beneficial bacteria involved in oxidizing ammonia to relatively safe nitrate in the freshwater aquarium. Scientists call these organisms “nitrifying” bacteria and archaea. We will use the term “beneficial bacteria” for both the nitrifying bacteria and the nitrifying archaea. Below in this article, we try to explain the complex science of “beneficial bacteria”.

This information is not necessary for setting up new aquariums or running existing aquariums. But some like to delve into the science. Read on if you are so inclined. Just be prepared for a very boring, long-winded dissertation only true nerds such as the author will be interested in.

Dimidiochromis compressiceps OB Malawi Eye Bitter
Dimidiochromis compressiceps OB Malawi Eye Bitter
Beneficial Bacteria in Depth
From a pure science perspective there are a whole series of “beneficial bacteria”, with more being discovered every year.

“Ammonia-oxidizing archaea and complete ammonia-oxidizing Nitrospira in water treatment systems”, Al-Ajeel 2022

“The sequential steps of this respiratory process are carried out by distinct microbial guilds, including ammonia-oxidizing bacteria (AOB) and archaea (AOA), nitrite-oxidizing bacteria (NOB), and newly discovered members of the genus Nitrospira that conduct complete ammonia oxidation (comammox). Even though all of these nitrifiers have been identified within water treatment systems, their relative contributions to nitrogen cycling are poorly understood. Although AOA contribute to nitrification in many wastewater treatment plants, they are generally outnumbered by AOB. In contrast, AOA and comammox Nitrospira typically dominate relatively low ammonia environments such as drinking water treatment, tertiary wastewater treatment systems, and aquaculture/aquarium filtration.”

So the bottom line appears to a combination of bacteria and archaea are present so Ph will effect nitrification.


It can affect nitrification but as the microbial assemblage is constantly changing based on ammonia, levels, pH, oxygen, even livestock the predominant microbes in aquariums filters are are Archaea.

Unfortunately we just can’t blanket statement that pH stalls nitrification because the microbial suite is adapting to the environment constantly. Plenty of material here.

https://www.ukaps.org/forum/threads/does-depleted-kh-stop-the-nitrogen-cycle.71239/

How rubbish nature would be if it couldn’t figure this out by now.
 
It can affect nitrification but as the microbial assemblage is constantly changing based on ammonia, levels, pH, oxygen, even livestock the predominant microbes in aquariums filters are are Archaea.

Unfortunately we just can’t blanket statement that pH stalls nitrification because the microbial suite is adapting to the environment constantly. Plenty of material here.

https://www.ukaps.org/forum/threads/does-depleted-kh-stop-the-nitrogen-cycle.71239/

How rubbish nature would be if it couldn’t figure this out by now.

Thank you Caliban07,

I am getting a hint of nitrates with the NTlabs liquid (between 0-5ppm).

I have also checked my KH as it's also between 0-1. Here in the Isle of Man is no more than 2.
I added last week crushed coral to my external filter as I previously mentioned to increase the Ph (6.4 now) but my Kh is still low.
Will the crushed coral increase also the Kh in my tank?
 
Thank you Caliban07,



I am getting a hint of nitrates with the NTlabs liquid (between 0-5ppm).



I have also checked my KH as it's also between 0-1. Here in the Isle of Man is no more than 2.

I added last week crushed coral to my external filter as I previously mentioned to increase the Ph (6.4 now) but my Kh is still low.

Will the crushed coral increase also the Kh in my tank?


Don’t worry about the KH. My KH is the same. My tap water comes from the reservoirs in the Lake District and is naturally very soft.

Crushed coral in theory will raise pH initially because the water will be acidic enough to break parts of it down. As the calcium carbonate dissolves and goes in to solution the KH will increase. This increase in KH will raise the pH slightly but only until a point the where the water is no longer acidic enough to break the coral down. At this point think of it like a battery on trickle charge. As voltage is removed from the battery it is immediately topped back up to the initial starting voltage. If your pH has risen slightly, the new level is like the starting voltage. As the carbonate hardness runs down the pH will fall, erode the coral and the coral will release carbonates stabilising pH again. This process will be happening all the time that you just will not be able to capture it on a test.

The best way to manage KH is with weekly water changes or by adding a soluble carbonate component like potassium bicarbonate or potassium carbonate but I wouldn’t bother. It’s just not that important unless you’re trying to keep species that prefer harder water.
 
It can affect nitrification but as the microbial assemblage is constantly changing based on ammonia, levels, pH, oxygen, even livestock the predominant microbes in aquariums filters are are Archaea.

Unfortunately we just can’t blanket statement that pH stalls nitrification because the microbial suite is adapting to the environment constantly. Plenty of material here.

https://www.ukaps.org/forum/threads/does-depleted-kh-stop-the-nitrogen-cycle.71239/

How rubbish nature would be if it couldn’t figure this out by now.
Interesting discussion but the Expert dw1305 continually posts things that say the the presence of BOTH archaea and commonox nitrospira occur and this is from the a 2022 paper on effects of ph on commonox nitrospira from the Institute of health: The results indicated that soil pH was an important factor in shaping Comammox Nitrospira community structure. Comammox Nitrospira were detected in all soil samples, and Comammox clade A had a preference for acidic environments. It seemed that species from N. nitrosa possessed the ecological niche of low pH environments, whereas species from N. inopinata preferred to live in neutral environments. In conclusion, pH had a significant effect on the abundance and community structure of Comammox Nitrospira, which was one of the important factors affecting the niche differentiation of Comammox Nitrospira.
full article here: https://pubmed.ncbi.nlm.nih.gov/35393844/

This says to me that full nitrification can not occur ( or occurs more slowly) in low Ph water UNLESS strains of nitrospira clade A are present but that happening is dependent on the environment in which the cultures were formed. If they don't start out in low Ph water, you more than likely get Clade B which did not do well in low Ph environment. :huh: ;)
 
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