Fishless cycle 3 weeks in

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Bpd1

Aquarium Advice Apprentice
Joined
Jun 12, 2022
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Cycling a tank at the minute in completed week 3. Added some gravel from an existing established tank. I'm dosing ammonia to 2ppm resulting in test to less than 1ppm in 24 hrs but nitrite is reading zero last 3 days in 24hrs. Is this something that happens? Is it possibly from the gravel and is normal?
 
Ammonia going down by 1ppm would normally lead to nitrite increasing by 2.7ppm.

A few reasons why it might not.

- Your testing is inaccurate. Are you sure you are doing the test correctly?
- Your cycle is established enough to turn the nitrite into nitrate. Have you tested for nitrate?
- Your cycle isnt established at all yet and the ammonia is being taken up by plants. Do you have any plants in the tank.

Or maybe a little of all three.
 
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Ammonia going down by 1ppm would normally lead to nitrite increasing by 2.7ppm.

A few reasons why it might not.

- Your testing is inaccurate. Are you sure you are doing the test correctly?
- Your cycle is established enough to turn the nitrite into nitrate. Have you tested for nitrate?
- Your cycle isnt established at all yet and the ammonia is being taken up by plants. Do you have any plants in the tank.

Or maybe a little of all three.
- Your ammoni

Left out that key piece of info. Yeah Nitrate off the chart. Definitely testing correctly. Plagued you aiken about 6 months back about cycling a different tank. Just thought it odd that nitrite might be cycling out quicker than ammonia
 
I wouldnt worry about it. Its not usual but its whats happening. Just wait it out, when you can cycle out 2ppm to zero ammonia and nitrite in 24 hours you are cycled enough to moderately stock fish.

2ppm is more ammonia than a tank full of fish will produce. Possibly the gravel you used hasnt seeded enough microbes to cycle out all that ammonia, but has enough to cycle out the nitrite.

Skip a day ammonia dosing. See if the ammonia goes down if you arent adding any new.
 
I wouldnt worry about it. Its not usual but its whats happening. Just wait it out, when you can cycle out 2ppm to zero ammonia and nitrite in 24 hours you are cycled enough to moderately stock fish.

2ppm is more ammonia than a tank full of fish will produce. Possibly the gravel you used hasnt seeded enough microbes to cycle out all that ammonia, but has enough to cycle out the nitrite.

Skip a day ammonia dosing. See if the ammonia goes down if you arent adding any new.

Thanks Aiken
 
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