Water cycle explanation?

Meyer Jordan

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The term cycling as applies to ponds focuses to that part of the overall Nitrogen cycle where the Ammonia secreted by fish and decaying organic matter is first converted into Nitrite by specialized bacteria, which in turn is converted into Nitrate also by specialized bacteria. This is emphasized in pond care because both Ammonia and Nitrite become toxic and deadly to fish at certain levels. A 'cycled' pond refers to a pond that has the necessary population levels of these specialized bacteria to prevent any toxic accumulations
 

Mmathis

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---- Yes, I know this is super simplified -- no comments, please! ----

1). Fish produce ammonia. Ammonia is toxic.

2). Bacteria break down the ammonia into nitrites. Nitrites are toxic.

3). A different type of bacteria breaks down nitrites into nitrates. Nitrates are the end product. They can be toxic in large amts. Plants and water changes will eliminate nitrates.

When your pond is first starting, it starts with ammonia in the water [from the fish waste]. The bacteria are already present, so the presence of the ammonia gets them started -- at this point all you'll have is ammonia.

Then once the ammonia starts being converted to nitrites, you'll have some ammonia and nitrites. Then the bacteria that convert the nitrites (they are already present in the water) kick in and do their thing -- they convert nitrites to nitrates.

You'll know that your pond is "cycled" once you see the presence of ammonia, followed by the presence of nitrites, then nitrates, in that order -- you have to test your water. Once all of those 3 chemicals return to "0" ppm, your pond is cycled. This takes weeks to happen. It's not an overnight thing. And you'll probably have an algae bloom during this time, which is normal and will go away on its own.

And you have to start with a very low fish load, and gradually increase the number of fish you have. If you start off with too many fish, your levels will rise too high, too fast.....which can cause harm or death to your fish. Even if they don't SEEM to be injured, high ammonia levels can cause gill damage.

The bacteria is already present in the water -- if just needs the presence of the right chemicals for the processes to take place. There is really nothing that YOU need to add. Mother Nature will take care of it for you. Don't waste your money on products that claim to contain beneficial bacteria.
 

DutchMuch

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Cycling is when you have/grow/enough beneficial bacteria in your biological filtration system (Nitrifying bacteria).
These bacteria remove Ammonia, and Nitrite from the water column creating there waste that is Nitrate. Nitrate is then obsorbs by plants you have in the pond or hanging into your pond.
Nitrite and ammonia are toxic to fish and can stress them out, this causes proneness to disease or fungus growth on/in the fish.

You can cycle your pond by doing an in fish cycle:
And in fish cycle is where you have your filtrations system not yet cycled with nitrifying bacteria growing on it, and you add the fish to the water anyway. The fish produce the Nitrite and Ammonia for the beneficial bacteria colony to begin growing in your biological filtration system. Slowly reaching a large enough colony to sustain your fish or inhabitants. However an in fish cycle is risky in all cases, because it can stress the fish out leaving them again prone to disease or fungus growth. And is just uncomfortable to them.

You can also do a fishless cycle:
Fishless cycle is where you have your biological filtration setup on/in your pond but you do not have fish in the pond to produce ammonia or nitrite. There are multiple ways you can support ammonia and nitrite in your pond still, by adding food, or adding special products made for this situation. This is a more commonly used practice as it doesn't stress out your fish, because they aren't there yet. But when you add them and acclimate them to your ponds water, they will be way less prone to disease/fungus growth.
 

ZEROPILOT

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So...my pond has cycled and my nitrite level is 0.
Ammonia Is a trace or less than o.25 ppm
My nitrate level, however us about 25, 30 ppm.
Is this normal?
The fishes are all very active and my ph is stable at 8.0
 

Jhn

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Yes, that is normal. If you get a decent amount of plants going in the pond, will help lower the nitrate as well. ( dependant on keeping a balanced fish load)
 

ZEROPILOT

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I've got two pretty large, planted water lilies. But they've only been in there a few days.
So, I'll watch the nitrates and prepare to do a partial water change if it keeps climbing? Or should they settle down too now that the nitrites are gone?
 

IPA

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I've got two pretty large, planted water lilies. But they've only been in there a few days.
So, I'll watch the nitrates and prepare to do a partial water change if it keeps climbing? Or should they settle down too now that the nitrites are gone?
Many say water lily don't draw a lot of nutrients, nitrate for them, from the water compared to other plants. As the good algae takes hold on surfaces it will use much of the nitrates for nutrients. I say keep up water changes until that begins to happen. You could also add a container with plants in or out of pond flowing water through it to pull the nitrates and phosphate. Could even be temporary.
 

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