Nitrogen cycle tracker
Enter the date you set up the tank and your test results. The tracker shows the cycle stage, what is still missing and the next step.
Where your cycle is
Enter the set-up date to see your cycle stage.
This is a hint based on your readings, not a guarantee.
Add two or more tests to see the trend.
No tests yet.
Runs entirely in your browser. Nothing you enter is sent to a server.
How it works
A new aquarium has no colony of beneficial bacteria yet. Fish waste and leftover food release ammonia, which is toxic to fish. Over the first weeks one group of bacteria turns ammonia into nitrite, which is also toxic, and a second group turns nitrite into nitrate. Nitrate is far less harmful and is removed with regular water changes. This is the nitrogen cycle.
The tracker treats readings of 0.25 ppm or less as zero, because that is the smallest step most drop and strip tests can show. A tank counts as cycled only when four things are true: it is at least 14 days old, the last two tests in a row show ammonia and nitrite at zero, those tests are at least 3 days apart, and at least one of them shows nitrate above zero, which proves the bacteria are working.
A fishless cycle usually takes 3–6 weeks. Test every 2–3 days, keep the filter running, and don't rinse the filter media in tap water while the tank cycles. Your entries are stored only in this browser.
Frequently asked questions
Usually 3 to 6 weeks without fish. Water temperature, the ammonia source and whether the filter was seeded with media from an established tank all change the pace.
Zero ammonia and nitrite can also mean nothing is feeding the bacteria yet. Nitrate appearing shows that the second stage of the cycle is really converting nitrite.
Yes, but gradually: a few fish at a time with a week or two between additions, and keep testing. The bacteria colony grows with the load it receives.
Keep track in Aquairi
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