How do you know

[Little Guys]

I thought my tank is cycling and then some comments in another post made me wonder.  How do you know if it is cycling?  What do the numbers do?

[Tony s]

For a fully cycled tank. You need 0 ammonia, 0 nitrite, and some nitrate. If you don’t have any nitrate, it’s either very planted or not cycled at all. 
 

there are 3 main strategies for cycling a tank. All are successful. All require some form of living beneficial bacteria to be added. 
usually fritzyme7, Dr Tim’s, api QuickStart, or seachem stability.

then you need a form of ammonia. Either live fish, or ammonium chloride, or fish food that’s rotting in the bottom of the tank creating ammonia. 
 

then you add in your bacteria and wait. The ammonia witch is poisonous converts to nitrite. Which is also poisonous. The nitrite in turn converts to nitrates . Which are not as poisonous and the fish can live in. Hence you’re looking for 0ammonia. 0 nitrite, and some amount of nitrates.  If you choose to do your cycle with live fish. You need to constantly check your water for ammonia and nitrite. If you see any you need to do a water change. By siphoning out old water and replacing it. Then you need to add a dechlorinator like prime. Because city water has chlorine to kill bacteria in the water. The constant water checks will ease over time as the tank becomes cycled. Then the only thing you should see is nitrate. Nitrates should be kept around 20. The only thing to remove nitrates are plants and water changes. Try these videos 

 

[Little Guys]

I do understand the nitrogen cycle.  However I have fish and lots of plants.  I almost always have  10 Nitrate and 0 Nitrite when I test.  I have never had amonia when I test and that is what makes me ask the question.  So, Is my tank not cycled OR are the plants taking care of it?  How do I know?

[Pepere]

On 3/19/2024 at 1:16 AM, Tony s said:

there are 3 main strategies for cycling a tank. All are successful. All require some form of living beneficial bacteria to be added. 
usually fritzyme7, Dr Tim’s, api QuickStart, or seachem stability.

If you dont add bacteria in a bottle product, , your tank will still cycle…. The spores are airborne in the air we breathe. They are in the ground , and in the potting soil in your houseplants.   The very best such bacteria in a bottle products can do is save you a tiny amount of time verses just adding ammonia to your tank and waiting…

My experience with such products have not convinced me they save any measurable amount of time.

As to how can you tell if your tank is cycled?  Yes, 0 ammonia, 0 nitrites, and some nitrates, assuming you placed an ammonia source in the tank, either ammonia or food that rotted and caused ammonia to form, and no nitrates weee in the tank, does indicate you have both forms of bacteria in the tank…. But, the question remains as to how much ammonia can the tank process in a given amount of time?

 

Does it take 24 hours or does it take a week to process 2 ppm ammonia challenge  to 0 ammonia and 0 nitrates?

If it takes 24 hours, your beneficial bacteria can handle a reasonable bioload.  If it takes a week, not so much…

[Pepere]

On 3/19/2024 at 1:33 AM, Little Guys said:

However I have fish and lots of plants.  I almost always have  10 Nitrate and 0 Nitrite when I test.  I have never had amonia when I test and that is what makes me ask the question.  So, Is my tank not cycled OR are the plants taking care of it?  How do I know?

Well, it is a distinction without a difference sort of.  I mean if either the plants or the beneficial bacteria colony are able to handle fully the livestocks bioload being produced,   All is good.  Fish poo is very rich in beneficial bacteria and seeds a tank far more reliably than bacteria in a bottle products.  
 

How long have you had fish in your tank? How many fish, how many gallons?  How long have you had fish in the tank?

[Tony s]

On 3/19/2024 at 1:33 AM, Little Guys said:

10 Nitrate and 0 Nitrite when I test.  I have never had amonia when I test and that is what makes me ask the question.  So, Is my tank not cycled OR are the plants taking care of it?  How do I know?

Short answer, yes, you are definitely cycled. Fish produce ammonia, then the two types of bacteria reduce that twice into nitrite then nitrate. Nothing else in the tank actually produces nitrate but the cycling bacteria. The plants keep that low, as well as helping on ammonia and nitrites. But if you’re seeing nitrate at all you’re definitely cycled. And probably well seasoned.

[Flumpweesel]

Just keep in mind that as the plants are part of your cycle any drastic plant removal may cause a short term wobble in the tank balance but it should recover fast.  

[lefty o]

ill tell ya what, quit thinking of it as cycling, because it isnt, think of it as establishing the beneficial bacteria colony. sorry but the term is wrong and irritates me, cycling would be a circle and that means you end up right back where you started, and we dont want that. establish a bacteria colony, and the numbers will always bounce up and down a bit as they do their job breaking down waste.

[Schuyler]

On 3/18/2024 at 10:16 PM, Tony s said:

The ammonia witch

"I'll get you my pretty and your little fish too" 

Sorry... I just thought it was a funny typo 

On 3/18/2024 at 10:33 PM, Little Guys said:

So, Is my tank not cycled OR are the plants taking care of it?  How do I know?

Plants can be part of the nitrogen cycle. If your plants are growing and your but seeing ammonia or nitrates then your tank is probably established enough to start adding fish.

[Pepere]

On 3/19/2024 at 6:12 AM, Tony s said:

Short answer, yes, you are definitely cycled. Fish produce ammonia, then the two types of bacteria reduce that twice into nitrite then nitrate. Nothing else in the tank actually produces nitrate but the cycling bacteria.

Some tap water can have nitrate in it.  It would be reasonable to test tap water to know.  If your tap water is free of nitrates, than you definitely have a beneficial bacteria colony. 
 

knowing how big a bioload it can handle is another thing.  That is why it is good practice to increase livestock slowly and allow tank  to accommodate to new load.

[Little Guys]

Thank you all for your great information.  

Pepere - Tap water has no notrate.

Lefty O - Definately have bacteria.

Flumpweesel - I am a gardner and in more danger of putting too many plants in the tank.  Most recently fell in love with Dragon Claw.

Tony S - Tank is 5 months old and is coming along nicely.  I have had only one fish die, shrimp are breeding and so are the snails.

Schuyler - Watch out for flying monkeys. 

P.S.  The large snail shell is from a dead snail, I just liked the color.  Fish are hiding, I have Green Neon and Ember Tetras plus some Pygmy Corys and 2 Otos.