Fish In Nitrogen Cycle Simplified

mattgirl

Member
Fish in Nitrogen Cycle Simplified: No bottled Bacteria added

The cycle needs an ammonia source. In your case that ammonia source is your fish. They are in there eating, breathing and pooping. All those things produce ammonia. That ammonia is food for your cycle but can be deadly for the fish. You can't know how high the ammonia is without testing it. I highly recommend the API Master Freshwater Test Kit. With it you can know exactly what is happening with the tank water and can do water changes to keep the ammonia/nitrites down to safer levels. Without it you can't know how high the ammonia is so you need to be doing water changes every day to keep it down to a safer level.

A nitrogen cycle is simply growing ammonia and nitrite eating bacteria. That bacteria grows mostly on your filter media but also grows on every surface in your tank.

It takes time for the bacteria to start growing. The first bacteria is one that eats ammonia. The waste from the ammonia eating bacteria is nitrite. The second bacteria is one that eats nitrites. Then the waste from the nitrite eating bacteria is nitrate. There usually isn't another bacteria to eat the nitrates so they have to be removed with water changes. Nitrates are the final stage of the cycling process so unless you have them in your source water you probably won't see them until the nitrites rise and start to fall.

Right now the most important thing you can do to protect your fish is to keep the ammonia and nitrites (once they start showing up) as low as possible with water changes. Water changes will not hurt nor slow down the cycling process as long as you use a water conditioner in the water you are replacing and making sure the temp is close to the same as what you took out. The bacteria you are growing doesn't live in the water so changing it as often as necessary to protect the fish isn't detrimental to the cycling process. Removing a lot of the ammonia with water changes may slow the process down by a few days but is necessary to keep your fish safe. Getting the tank cycled is important but the safety of your fish has to be your top priority.

Ammonia can build up pretty fast so it is possible you will have to do water changes every day or every other day to keep it as low as possible. Low enough to not even show up in the test is ideal but is often difficult to achieve so try to keep it down to no more than .50

I both use and can't over stress the importance of SeaChem Prime while doing a fish in cycle. It is first and foremost a water conditioner but it has the added benefit of neutralizing low amounts of ammonia thus protecting your fish from its damaging affects yet leaving some there to feed the growing bacteria.

A fish in cycle is totally doable as long as your have a test kit, Prime, lots of time and a willingness to do as many water changes as needs to be done to make sure the fish are never in danger.

Contrary to some things I have read one never has to see an ammonia spike during the cycling process. While cycling my last tank I never saw an ammonia spike because I was doing 30% or more water changes every other day for most of the cycle and every day when the nitrites spiked. I know the ammonia was there because the tank did in fact cycle from a dry tank to a complete cycle within 6 weeks with no fish losses.
 
  • Moderator

Lucy

Moderator
Member
Thank you for writing this up mattgirl. It will be a great resource for those who cycle this way by choice or chance.
 

Mcewenstank

Member
So I basically just gotta keep doing what I have been, everyother day water changes and testing, until all levels are normal??
How so u test for nitrite and nitrates? Is there a test kit specifically for nitrite and nitrates?
 
  • Thread Starter

mattgirl

Member
Mcewenstank said:
So I basically just gotta keep doing what I have been, everyother day water changes and testing, until all levels are normal??
How so u test for nitrite and nitrates? Is there a test kit specifically for nitrite and nitrates?
I highly recommend the API Master Freshwater Test Kit. With it you can know exactly what is happening with the tank water and can do water changes to keep the ammonia/nitrites down to safer levels. In a fully cycled tank you will see 0 ammonia, 0 nitrites and some nitrates.
 

Amyjw

Member
Mcewenstank said:
So I basically just gotta keep doing what I have been, everyother day water changes and testing, until all levels are normal??
How so u test for nitrite and nitrates? Is there a test kit specifically for nitrite and nitrates?
Yes but the master kit has all the tests and it's actually cheaper to buy the big kit rather than all the components separatly
 

PlantZombie

Member
Hello, here I am, new to the hobby and trying to cycle my first tank using real plants. After one week, I am noticing melting as well as new growth. My water is getting very cloudy. BUT LAST NIGHT, MY GIRLFRIEND SUPRISES ME WITH 2 GLOFISH DANIOS.
Now I guess Im doing a fish-in cycle with live plants and I am a bit overwhelmed. I have API's freshwater master test kit, seachem prime, and have been dosing with seachem flourish advance since the beginning. I also used tetra safe start and complete water care kit in the begening.
My ph is dark blue. (Maybe 7.4 or 7.5?)
Amonia, nitrites, and nitrates are all 0ppm
THE QUESTION:
Am I overthinking things? Or is "time" now my friend and I just must relax and observe my levels?
 

Cory04

Member
  • Thread Starter

mattgirl

Member
PlantZombie said:
Hello, here I am, new to the hobby and trying to cycle my first tank using real plants. After one week, I am noticing melting as well as new growth. My water is getting very cloudy. BUT LAST NIGHT, MY GIRLFRIEND SUPRISES ME WITH 2 GLOFISH DANIOS.
Now I guess Im doing a fish-in cycle with live plants and I am a bit overwhelmed. I have API's freshwater master test kit, seachem prime, and have been dosing with seachem flourish advance since the beginning. I also used tetra safe start and complete water care kit in the begening.
My ph is dark blue. (Maybe 7.4 or 7.5?)
Amonia, nitrites, and nitrates are all 0ppm
THE QUESTION:
Am I overthinking things? Or is "time" now my friend and I just must relax and observe my levels?
Welcome to Fishlore

Yes, time, patience and a lot of water changes are in your immediate future. What was your ammonia source before you added the fish? Without one the cycle wouldn't have started until now.

What size is this tank? How long have you had it set up and running? Now that you have a couple of fish you should start getting an ammonia reading in a few days.
Cory04 said:
A fishless cycle is way more stress and headache free
It is but we are addressing fish in cycling here. To be perfectly honest with you though, I would stress over an empty tank more than while doing a fish in. I actually enjoy making sure my fish are never in danger. Personally I think we get a stronger more natural cycle when cycling with fish.

If we don't add bottled bacteria we know exactly what to expect and the cycle normally follows a fairly accurate timeline. By adding bottled bacteria all bets are off. We may skip the nitrite spike and often we can't depend on the numbers we are seeing. We can only guess at where we are in the cycle.

Too often I have seen folks finish a fishless cycle by feeding the tank liquid ammonia. Once they add fish they find the cycle wasn't strong enough and they find themselves doing a fish in cycle after all. I do have a thread about this and how to hopefully prevent it happening after doing a fishless cycle.
 

Amyjw

Member
PlantZombie said:
Hello, here I am, new to the hobby and trying to cycle my first tank using real plants. After one week, I am noticing melting as well as new growth. My water is getting very cloudy. BUT LAST NIGHT, MY GIRLFRIEND SUPRISES ME WITH 2 GLOFISH DANIOS.
Now I guess Im doing a fish-in cycle with live plants and I am a bit overwhelmed. I have API's freshwater master test kit, seachem prime, and have been dosing with seachem flourish advance since the beginning. I also used tetra safe start and complete water care kit in the begening.
My ph is dark blue. (Maybe 7.4 or 7.5?)
Amonia, nitrites, and nitrates are all 0ppm
THE QUESTION:
Am I overthinking things? Or is "time" now my friend and I just must relax and observe my levels?
Yup going thru the exact same smh. It will be fine tho.. thats what I keep telling myself
 

PlantZombie

Member
Thanks guys. Is there a rule of thumb with adding more fish over time, during a fish-in cycle? These two little guys are less than an inch and They are in a 20 gallon tank. (Not the long one)
 
  • Thread Starter

mattgirl

Member
PlantZombie said:
Thanks guys. Is there a rule of thumb with adding more fish over time, during a fish-in cycle? These two little guys are less than an inch and They are in a 20 gallon tank. (Not the long one)
I have to think if you are not seeing an ammonia reading after a week or so it would be safe to add a couple more. Personally I would go ahead and add at least 4 more right now but if you do so keep a very close eye on the ammonia. As long as you can keep it down to around .25 with water changes the cycle will grow and the fish should be safe.
 

Lomein

Member
mattgirl said:
Fish in Nitrogen Cycle Simplified: No bottled Bacteria added

The cycle needs an ammonia source. In your case that ammonia source is your fish. They are in there eating, breathing and pooping. All those things produce ammonia. That ammonia is food for your cycle but can be deadly for the fish. You can't know how high the ammonia is without testing it. I highly recommend the API Master Freshwater Test Kit. With it you can know exactly what is happening with the tank water and can do water changes to keep the ammonia/nitrites down to safer levels. Without it you can't know how high the ammonia is so you need to be doing water changes every day to keep it down to a safer level.

A nitrogen cycle is simply growing ammonia and nitrite eating bacteria. That bacteria grows mostly on your filter media but also grows on every surface in your tank.

It takes time for the bacteria to start growing. The first bacteria is one that eats ammonia. The waste from the ammonia eating bacteria is nitrite. The second bacteria is one that eats nitrites. Then the waste from the nitrite eating bacteria is nitrate. There usually isn't another bacteria to eat the nitrates so they have to be removed with water changes. Nitrates are the final stage of the cycling process so unless you have them in your source water you probably won't see them until the nitrites rise and start to fall.

Right now the most important thing you can do to protect your fish is to keep the ammonia and nitrites (once they start showing up) as low as possible with water changes. Water changes will not hurt nor slow down the cycling process as long as you use a water conditioner in the water you are replacing and making sure the temp is close to the same as what you took out. The bacteria you are growing doesn't live in the water so changing it as often as necessary to protect the fish isn't detrimental to the cycling process. Removing a lot of the ammonia with water changes may slow the process down by a few days but is necessary to keep your fish safe. Getting the tank cycled is important but the safety of your fish has to be your top priority.

Ammonia can build up pretty fast so it is possible you will have to do water changes every day or every other day to keep it as low as possible. Low enough to not even show up in the test is ideal but is often difficult to achieve so try to keep it down to no more than .50

I both use and can't over stress the importance of SeaChem Prime while doing a fish in cycle. It is first and foremost a water conditioner but it has the added benefit of neutralizing low amounts of ammonia thus protecting your fish from its damaging affects yet leaving some there to feed the growing bacteria.

A fish in cycle is totally doable as long as your have a test kit, Prime, lots of time and a willingness to do as many water changes as needs to be done to make sure the fish are never in danger.

Contrary to some things I have read one never has to see an ammonia spike during the cycling process. While cycling my last tank I never saw an ammonia spike because I was doing 30% or more water changes every other day for most of the cycle and every day when the nitrites spiked. I know the ammonia was there because the tank did in fact cycle from a dry tank to a complete cycle within 6 weeks with no fish losses.
Answered ALL of my questions! Thanks!!!
 
  • Thread Starter

mattgirl

Member
Lomein said:
Answered ALL of my questions! Thanks!!!
Welcome to Fishlore

I am very happy to hear it helped you out
 

PlantZombie

Member
I have been adding new fish once a week to my 20 gallon planted tank. I now have 7 little zebrafish. Its been almost a month into my fish-in cycle and I have not noticed an amonia spike, or a nitrite spike, and my nitrates still read 0ppm. Ive noticed some new growth in my brizilian pennywort, and with my S. Repens. I recently put black electrical tape on my beamswork lighting because of hair algae. And ive been preforming 10%-15% water changes every other day with seachem prime. I believe the rockwoll on my amazon sword is adding cilicates and phosphate to the watter so i also ordered some seachem phosguard.
I have a bunch of stone and driftwood for a re-scape and im curious if my ceramic rings and biofoam sponge has enough bacteria to maybe save 25%-50% of the old watter, take EVERYTHING out, re-scape, re-plant, and add the 7 fish back in once Im done.
I have a bottle of tetra safe start laying around, i may use it just to be safe???. Am I overlooking something important? Are re-scapes alloud after only 1 month into my fish-in cycle?
 
  • Thread Starter

mattgirl

Member
PlantZombie said:
I have been adding new fish once a week to my 20 gallon planted tank. I now have 7 little zebrafish. Its been almost a month into my fish-in cycle and I have not noticed an amonia spike, or a nitrite spike, and my nitrates still read 0ppm. Ive noticed some new growth in my brizilian pennywort, and with my S. Repens. I recently put black electrical tape on my beamswork lighting because of hair algae. And ive been preforming 10%-15% water changes every other day with seachem prime. I believe the rockwoll on my amazon sword is adding cilicates and phosphate to the watter so i also ordered some seachem phosguard.
I have a bunch of stone and driftwood for a re-scape and im curious if my ceramic rings and biofoam sponge has enough bacteria to maybe save 25%-50% of the old watter, take EVERYTHING out, re-scape, re-plant, and add the 7 fish back in once Im done.
I have a bottle of tetra safe start laying around, i may use it just to be safe???. Am I overlooking something important? Are re-scapes alloud after only 1 month into my fish-in cycle?
I normally don't recommend making any major changes until a cycle is well established. The first few months it is still fairly delicate. Since you are wanting to do a total rescape you will be removing a significant amount of bacteria since it grows on all the surfaces in our tanks. Should you decide to do the rescape just keep a close eye on the parameters once done.

I do have to wonder why you are doing so many of these small water changes. One big water change as needed normally works better than several small ones. In your case you are lightly stocked so I will recommend you keep an eye on the ammonia/nitrite levels and do water changes accordingly. If you are constantly seeing 0 ammonia and 0 nitrites hold off on the frequent water changes. It may actually be time for you to go to your weekly maintenance water changes.

When I cycled my tank I was doing much larger water changes and was doing them often but I was doing a fish in cycle with a fully stocked tank. In my case I knew there would be a lot of ammonia produced so needed to stay ahead of it. In your case you are lightly stocked so I will recommend you keep an eye on the ammonia/nitrite levels and do water changes according to your numbers.
I believe the rockwoll on my amazon sword is adding cilicates and phosphate to the watter so i also ordered some seachem phosguard.
Before adding any product to your tank you really need to be sure it is needed.
 

PlantZombie

Member
Thank you for your advice. I will hold off with adding product unless I am sure i need it. I think i should have waited for all my hardscape to arrive before starting my first tank.
I thought my frequent water changes were staying ahead of the amonia and helping to reduce algae, but i guess i should let the test kit tell me when to do water changes?
I am giving myself anxiety with all this hardscape sitting here waiting to go in... Lol!
 
  • Thread Starter

mattgirl

Member
PlantZombie said:
Thank you for your advice. I will hold off with adding product unless I am sure i need it. I think i should have waited for all my hardscape to arrive before starting my first tank.
I thought my frequent water changes were staying ahead of the amonia and helping to reduce algae, but i guess i should let the test kit tell me when to do water changes?
I am giving myself anxiety with all this hardscape sitting here waiting to go in... Lol!
Time and patience is the key to cycling our tanks. When we are doing a fish in cycle throw in water changes. In some cases lots of them

Yes, let your test kit be your guide. I do recommend weekly water changes no matter what the numbers are telling me though. With your 20 gallon with just 7 small fish and actively growing plants 30% weekly may be enough to change. 50% won't hurt though.
 

PlantZombie

Member
I am verry grateful for fishlore and all its members help and advice. This hobby is great and I know the waiting will pay off in the end. Eventually, I want to increase my bio load and have corys, ottos, or both as my bottom dwellers, and maybe some red melon sword, and ludwigia repens for color.
 

Jmanrow

Member
Amyjw said:
Yup going thru the exact same smh. It will be fine tho.. thats what I keep telling myself
I would recommend lowering your pH to 7.0, but not lower than 6.5
Ammonia is more toxic at higher pH. As you lower the pH it changes from free ammonia, to less harmful ammonium.
 

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