Ideal Ammonia Level For Fishless Cycling - Science?

[TobyZ28]

Is anyone aware of any study/test done with X identical uncycled tanks with identical filtration, at the same temperature with ammonia kept at a few varying levels to determine what ppm of ammonia is ideal for fishless cycling? So many people with multiple tanks out there there has to be someone that did a quazi-scientific test to determine this by now?

I have read opinions for ammonia kept anywhere from .25 - 8ppm. I've also heard warmer temperatures speed the process as well. Any experts able to point me to some science?

Anecdotal Evidence List:

• ~1ppm Ammonia / day seems like a reasonable "upper level" of ammonia to handle for a typical home aquarium.
• 1-2ppm seems to do just fine for fishless cycling
• Low KH/soft water may stall out/slow down the nitrification process. (I would imagine the lack of minerals may stall bacteria growth? Logical, but haven't seen any study on it) - See below for update on Phosphorus being critical.
• NightShade should sell his water for aquarists

Running Fact List on Cycle Related Conditions and Bacteria:

• The temperature for optimum growth of nitrifying bacteria is between 77-86° F (25-30° C).
• Growth rate is decreased by 50% at 64° F (18° C).
• Growth rate is decreased by 75% at 46-50° F.
• No activity will occur at 39° F (4° C)
• Nitrifying bacteria will die at 32° F (0° C).
• Nitrifying bacteria will die at 120° F (49° C)
• Nitrobacter is less tolerant of low temperatures than Nitrosomonas. In cold water systems, care must be taken to monitor the accumulation of nitrites
• The optimum pH range for Nitrosomonas is between 7.8-8.0.
• The optimum pH range for Nitrobacter is between 7.3-7.5
• Maximum nitrification rates will exist if dissolved oxygen (DO) levels exceed 80% saturation.
  
• Nitrification will not occur if DO concentrations drop to 2.0 mg/l (ppm) or less.
  
• Phosphorus is normally available to cells in the form of phosphates (PO4). Nitrobacter, especially, is unable to oxidize nitrite to nitrate in the absence of phosphates.
  
• Sufficient phosphates are normally present in regular drinking water.
  
• During certain periods of the year, the amount of phosphates may be very low. A phenomenon known as "Phosphate Block" may occur.
  
• If a source of phosphate needs to be added to the aquarium. Phosphoric Acid is recommended as being simplest to use and dose, however, either mono-sodium phosphate or di-sodium phosphate may be substituted. When using a 31% phosphoric acid mixture, apply a one time application of 1 drop per 4 gallons of water to activate the Nitrobacter.
  
• Nitrifying bacteria are photosensitive, especially to blue and ultraviolet light.
• 1 ppm ammonia --> 2.7 ppm nitrite --> 3.6 ppm nitrate.

A list of products claiming to contain true nitrifying bacteria are as follows:

• Colony Professional Grade Nitrifying Bacteria Marine Aquarium Supplement ()
• Colony Professional Grade Nitrifying Bacteria Freshwater Aquarium Supplement ()
• ATM (Acrylic Tank Manufacturing), Las Vegas, NV 89118
• ATM (Acrylic Tank Manufacturing) UK, Norwich NR10 3SS -
• ProLine Nitrifying Bacteria, Freshwater ()
• ProLine Nitrifying Bacteria, Saltwater ()
• Pentair Aquatic Eco-Systems, Inc., Apopka, FL 32703
• Aquatic Solutions Nitrifying Bacteria, Freshwater (Aquatic Solutions)
• Aquatic Solutions Nitrifying Bacteria, Saltwater (Aquatic Solutions)
• Aquatic Solutions, LLC, Des Moines, Iowa 50310
• One & Only Nitrifying Bacteria for Freshwater Aquaria (One & Only)
• One & Only Live Nitrifying Bacteria for Reef, Nano and Seahorse Aquaria (One & Only)
• DrTim's Aquatics, LLC, Moorpark, CA 93021
• Fritz Zyme #7 – TurboStart (Freshwater)
• Fritz Zyme #9 – TurboStart (Saltwater)
• Fritz Industries - Fritz Pet Products, Dallas, TX 75149

Sources:
Nitrifying Bacteria Facts (SUPER awesome article jammed with facts)

 

[AllieSten]

is a great resource for the science of things. He has been caring for fish, for several decades. Maybe he can help point you in the right direction.

 

[NavigatorBlack]

I am one of the people here who pay attention to fish evolution, habitat and natural history, and try to keep up on the research. But I have never done a fishless cycle, and haven't owned a test kit since some time in the early 1990s. I've never bought ammonia.

I regretfully crashed one fish in cycle 30 years ago, and have never had a cycling issue since. I'd never had one before, either. I test for pH, tds, and hardness, but my water chemistry interest ends there.

The OP's question is a call out for a chemistry student with a few tanks.

 

[OnTheFly]

Interesting question and I hope you get a scientific answer. Most, if not all of what we read on the net is anecdotal. It seems that BB capable of processing 2ppm of ammonia in 24HRs will accept a full stocking of fish without spiking. 2ppm seems to be the equivalent of a very heavy stocking of fish. It's been more than adequate in my experience. To be more scientific would require us to know the ammonia output of the fish species given food consumption. Both food type and amount would be relevant. It would be a complicated experiment if you were in search of a precise answer.

 

[TobyZ28]

Thanks for the reply NavigatorBlack! I'm 50% into this hobby to learn, and 50% to have fun! I do have a tangent question (if I'm allowed to hijack my own thread!), for soft water like Vancouver (7.9 - 11.8ppm or <1 dKH) should I be treating it with anything for water changes(assuming a nothing too fancy regular fish tank)? I'd like to aI'm away from jogj cost products (if possible!).

 

[TobyZ28]

Interesting question and I hope you get a scientific answer. Most, if not all of what we read on the net is anecdotal. It seems that BB capable of processing 2ppm of ammonia in 24HRs will accept a full stocking of fish without spiking. 2ppm seems to be the equivalent of a very heavy stocking of fish. It's been more than adequate in my experience. To be more scientific would require us to know the ammonia output of the fish species given food consumption. Both food type and amount would be relevant. It would be a complicated experiment if you were in search of a precise answer.

Yes! I've found a tonne of anecdotal information out there, sometimes going down rabbit holes for pages before someone realizes an early assumption threw everything else off. I agree though that it could be a complicated experiment for a complete answer, with it reproduced by others for throughness. A simple/crude starting point though would be 3-4 tanks with only one parameter changing such as ammonia and careful monitoring through the cycle (then repeat the test with a different variable etc). I mean this MUST have been done a 1000x over by students/marine biologists right? I'd gladly do this if I had the space! The equipment doesn't need to be too fancy, just near identical.

2ppm does sound like a "safe" level to aI'm for, I'm just curious if keeping at 4 or 8ppm would increase or decrease the time it takes for a tank to be able to process 2ppm in 24 hrs to nitrates.

 

[NavigatorBlack]

Thanks for the reply NavigatorBlack! I'm 50% into this hobby to learn, and 50% to have fun! I do have a tangent question (if I'm allowed to hijack my own thread!), for soft water like Vancouver (7.9 - 11.8ppm or <1 dKH) should I be treating it with anything for water changes(assuming a nothing too fancy regular fish tank)? I'd like to aI'm away from jogj cost products (if possible!).

That dream water of yours is not going to cycle normally, if I understand the chemistry. What's the 7.9? I'll ask any chemically inclined readers to comment there.
With that little buffering, it will probably be acid, and in acid water, toxic ammonia is no major problem. The cycle produces less toxic ammonium.

That's dream tetra, rainforest fish, killie or other softwater species water. I thought I was lucky with 60 to 80ppm. But it is unstable, and will be very unforgiving if you miss a weekly water change, overstock, or don't choose your creatures very carefully. It opens up a world of fish that will love it, but closes doors on groups like MalawI Cichlids, commercial livebearers and other hard water evolved species and groups.

I would choose the fish for the water, rather than doctoring it, and make sure any chloramines are neutralized with any water changes. If you start changing the water with minerals to raise the GH/KH/pH, then you will need to study the water chemistry, and keep a close on on the changes you make.

I'm in 100% to learn, and 100% to have fun, since I can't separate the two. I'm into my 51st year of fishkeeping, and still find intriguing questions on a regular basis.

 

[AllieSten]

Thanks I knew that you didn’t test your tanks, and hadn’t for years. I just thought you would definitely have some good advice at least. And you certainly did.

 

[GlassyD]

I've been doing cycling experiments for a few years, and I think the reason there is no simple answer is that it depends so much on stocking level, feeding & etc. The early fishless cycling instructions sometimes had people cycling the filters up to 4 ppm per day of ammonia, which is much more than is needed. This might be a good starting level, but I have found that the average fish tank (...if there is such a thing) has a bioload that corresponds to more like 1.0 or 1.5 ppm ammonia per day.


There is a way to approach this question, which is to measure the rate at which nitrate builds up. In a tank that has no plants, the daily increase of nitrate divided by 3.4 tells you how much ammonia is being generated daily. For example, if your nitrate climbs from 10ppm to 30ppm in a week, that means 20ppm of nitrate came from about 6ppm of ammonia, which is close to 1 ppm ammonia per day.


I would say that if you plan to stock a 75 gallon tank with 6 large discus all at once, you should cycle up to at least 2ppm per day. Three smaller fish in a 20 gallon tank might only need 1 ppm. In most cases 1 ppm is enough to prevent mini-cycle.


There have been times when I needed to move a sick fish into a hospital tank that had no biofilter. After 24 hours I would measure the amount of accumulated ammonia and extrapolate from that.

 

[AvalancheDave]

There are a lot of studies on nitrification due to its usage in wastewater treatment (nitrate is a lot safer to release into waterways than ammonia). There are also a lot of studies due to aquaculture.

One idea is to simulate the levels of ammonia you'll see when fish is best. That's usually a low level of ammonia with a spike ~2 hours after each feeding. I measured ammonia at 0.40 about 2 hours after feeding but 0.05 the next morning right before feeding. Any excess nitrifer population will starve anyway.

On the other hand, maybe nitrification rate or nitrifer growth is enhanced at higher ammonia concentrations.

 

[OnTheFly]

Yes! I've found a tonne of anecdotal information out there, sometimes going down rabbit holes for pages before someone realizes an early assumption threw everything else off. I agree though that it could be a complicated experiment for a complete answer, with it reproduced by others for throughness. A simple/crude starting point though would be 3-4 tanks with only one parameter changing such as ammonia and careful monitoring through the cycle (then repeat the test with a different variable etc). I mean this MUST have been done a 1000x over by students/marine biologists right? I'd gladly do this if I had the space! The equipment doesn't need to be too fancy, just near identical.

2ppm does sound like a "safe" level to aI'm for, I'm just curious if keeping at 4 or 8ppm would increase or decrease the time it takes for a tank to be able to process 2ppm in 24 hrs to nitrates.

More anecdotal coming right at you.....

I cycle tanks with about 2ppm, but test them a time or two at 4ppm dose just because. My water cycles fairly fast, even without adding seasoned media. I have nitrites in about a day. But the nitrite bacteria grows much slower (which is normal). When I dose higher than 2ppm all I seem to accomplish is the mother of all nitrite spikes. It's off the API charts. I let it ride a week and see no further cycle progress. Perhaps I am stalling the cycle? Who knows, but if I do a near 100% WC to clear nitrites I am suddenly cycled in a day or so. It's happened time and time again. I suspect the practical answer is the experiment needs to happen in our own tanks, and figure out what works for us. The only thing I am certain of is a 2ppm dose is fine for my water. I can add as many fish as I want and parameters remain perfect. I believe you can set up 50 tanks and share your experience. It may or may not fully apply for mine. It's a fact different water cycles on it's own schedule. 100s of threads here verify that to my satisfaction, scientific or not.

 

[NightShade]

More anecdotal coming right at you.....

I cycle tanks with about 2ppm, but test them a time or two at 4ppm dose just because. My water cycles fairly fast, even without adding seasoned media. I have nitrites in about a day. But the nitrite bacteria grows much slower (which is normal). When I dose higher than 2ppm all I seem to accomplish is the mother of all nitrite spikes. It's off the API charts. I let it ride a week and see no further cycle progress. Perhaps I am stalling the cycle? Who knows, but if I do a near 100% WC to clear nitrites I am suddenly cycled in a day or so. It's happened time and time again. I suspect the practical answer is the experiment needs to happen in our own tanks, and figure out what works for us. The only thing I am certain of is a 2ppm dose is fine for my water. I can add as many fish as I want and parameters remain perfect. I believe you can set up 50 tanks and share your experience. It may or may not fully apply for mine. It's a fact different water cycles on it's own schedule. 100s of threads here verify that to my satisfaction, scientific or not.

I agree that the answer depends on our various tanks, for sure!

OnTheFly, totally jealous that you can cycle that fast!! LOL What's your KH, GH & TDS? I wonder what it is that makes it easier to cycle? Do you have chloramines in your water? Wonder if it's just the availability of bacteria. (That's what I would assume is most likely, but the information asked for above makes a difference ~ as I know you know! )

 

[OnTheFly]

I agree that the answer depends on our various tanks, for sure!

OnTheFly, totally jealous that you can cycle that fast!! LOL What's your KH, GH & TDS? I wonder what it is that makes it easier to cycle? Do you have chloramines in your water? Wonder if it's just the availability of bacteria. (That's what I would assume is most likely, but the information asked for above makes a difference ~ as I know you know! )

I have a well and live across the highway from a limestone quarry. No chlorine or chloramines. My GH tests 35 drops, My KH won't measure before 50 drops. That scared me for a long time but it's garbage data. My TDS would have to be 1500+ but it's not. It's 250-400 seasonally. 90% of my TDS is calcium carbonate. Cycle friendly. I will always keep some live-bearers and other hardwater lovers so I don't have to mix RO in all my tanks. I don't trust the API kit for extreme hard water. It gives reasonable test results when well is mixed with a LOT of RO.

 

[NightShade]

I have a well and live across the highway from a limestone quarry. No chlorine or chloramines. My GH tests 35 drops, My KH won't measure before 50 drops. That scared me for a long time but it's garbage data. My TDS would have to be 1500+ but it's not. It's 250-400 seasonally. 90% of my TDS is calcium carbonate. Cycle friendly. I will always keep some live-bearers and other hardwater lovers so I don't have to mix RO in all my tanks. I don't trust the API kit for extreme hard water. It gives reasonable reasonable test results when well is mixed with a LOT of RO.

Ahh... yes. I remember your water now. Brain fart (symptom of the flu LOL)

 

[TobyZ28]

I have a well and live across the highway from a limestone quarry. No chlorine or chloramines. My GH tests 35 drops, My KH won't measure before 50 drops. That scared me for a long time but it's garbage data. My TDS would have to be 1500+ but it's not. It's 250-400 seasonally. 90% of my TDS is calcium carbonate. Cycle friendly. I will always keep some live-bearers and other hardwater lovers so I don't have to mix RO in all my tanks. I don't trust the API kit for extreme hard water. It gives reasonable reasonable test results when well is mixed with a LOT of RO.

I literally laughed at @Nightshades comment and was picturing you living at the edge of a river coming out of a mountain range doing watcher changes with a bucket in the river, a few minutes you post a reply that's not that far off!

I'm out in Vancouver with very soft water which has very very low mineral content / other stuffs - which is great for drinking but not so great for aquariums I'm finding out!

 

[OnTheFly]

I literally laughed at @ Nightshades comment and was picturing you living at the edge of a river coming out of a mountain range doing watcher changes with a bucket in the river, a few minutes you post a reply that's not that far off!

I'm out in Vancouver with very soft water which has very very low mineral content / other stuffs - which is great for drinking but not so great for aquariums I'm finding out!

Kudos to you on your knowledge of geology. I can drive to the MississippI River in 30 seconds. Limestone Bluffs line the shore on the upper end of the river. My well is 376ft deep in a futile attempt to get far enough below the liquid rock. They charge by the foot to drill through solid rock so we call it good and buy a water softener so we don't get kidney stones. It's actually not that bad for humans, and guppies lol.

 

[NightShade]

I literally laughed at @ Nightshades comment and was picturing you living at the edge of a river coming out of a mountain range doing watcher changes with a bucket in the river, a few minutes you post a reply that's not that far off!

I'm out in Vancouver with very soft water which has very very low mineral content / other stuffs - which is great for drinking but not so great for aquariums I'm finding out!

No space between the @ symbol and the members name to tag

LOL!! I get a similar picture in my head when people say they have hard water!!

I've got similar water to you. 2° both KH and GH. TDS is usually around 40-60 iirc out of tap.

 

[AvalancheDave]

I have a well and live across the highway from a limestone quarry. No chlorine or chloramines. My GH tests 35 drops, My KH won't measure before 50 drops. That scared me for a long time but it's garbage data. My TDS would have to be 1500+ but it's not. It's 250-400 seasonally. 90% of my TDS is calcium carbonate. Cycle friendly. I will always keep some live-bearers and other hardwater lovers so I don't have to mix RO in all my tanks. I don't trust the API kit for extreme hard water. It gives reasonable test results when well is mixed with a LOT of RO.

Tests kits are going to express kH and gH in terms of the weight of the entire molecule while TDS measures just the ion (Ca2+, etc.). If you figure that in then your gH and kH values are a lot closer to your TDS.

 

[TobyZ28]

That dream water of yours is not going to cycle normally, if I understand the chemistry. What's the 7.9? I'll ask any chemically inclined readers to comment there.
With that little buffering, it will probably be acid, and in acid water, toxic ammonia is no major problem. The cycle produces less toxic ammonium.

The 7.9 - 11.8 was the ppm measure of water hardness range based on link (look for Vancouver, second lowest reading of any city in BC!). Using the (I think) more common dKH, it converts to less than 1 dKH. I'll factor in getting fish around the water here for sure!

I had Cycled water for a 5G with fish that took a solid 4 weeks here! I'm sure I was slowing it down with frequent water changes for the fishes benefit though.

I'm fishless cycling a 30G and am hoping (like everyone) for it to go as quickly as possible. I did seed with some media from the 5g, and I'm only on day 4 for the new tank with ammonia @4ppm. Things i've learnt so far:

• ~1ppm Ammonia / day seems like a reasonable high of ammonia to handle for a home aquarium.
• We don't definitively know what ppm to cycle a tank at is quickest. Anecdotally 1-2ppm would probably do just fine.
• Enough anecdotal evidence to suggest warm temperatures / good oxygenation help significantly (how much is still not known)
• Low KH/soft water may stall out/slow down the nitrification process. (I would imagine the lack of minerals may stall bacteria growth? Logical, but haven't seen any study on it).
• Through readings, nitrifying bacteria don't easily die off, they just go dormant / are less efficient under non-ideal conditions.
• NightShade should sell his water for aquarists

I haven't tested TDS here (i'm quite sure it's also very low) nor have I done much to understand TDS readings at all. I think I'll focus on that tonight!

 

[NavigatorBlack]

A lot of our readings are based on what is easy to read. We want numbers, but to keep them simple. That's where I believe the whole issue of over reliance on master test kits comes from - they are painfully incomplete but easy to use. They are kind of satisfying, in a way.
I can guess what's going on in a tank via tds, because reasonably reliable tds meters are cheap and simple to use.
A lot depends on your purpose for testing. I like rainforest fish whose eggs and sperm would be damaged or killed by water with a high mineral content. My breeder's approach will be different from that of an aquarist who wants as crowded a community tank as he can get away with.
It is science based, but not scientific. I don't test anything with controls or the basic methods any researcher would use. I get the water to where I want it based on crude readings, and then the real experts in water quality, the fish, breed. If they don't breed, then my crude readings and improvised techniques lead to more adjustments, and then some, til I get it to where I have success (or where other breeders have reported success - there is research to be done.)
A lot of aquarists I really respect spend a lot of time with the chemical kits, and they take a lot of knowledge away from them. The chemistry isn't my interest - except as it affects the biology of the organisms I am keeping.
There is a lot of fun to be had with that learning too though.