Is my cycle right?

Beth_obrien2424

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I am currently cycling a tank ready for some fry to go into when the tank is ready.
I am doing a fishless cycle and bought ammonia for it. I followed the directions on the package for the ammonia (10 drops for every gallon).
now, my ammonia levels are back at 0ppm but both the nitrite and nitrate are very high. Is this normal? I know it goes in stages but on my previous tank the ammonia was the second thing to drop to 0ppm
 

essjay

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Yes it is normal. Having nitrite fall before ammonia is unusual.

Cycling is a 2 stage process, growing the ammonia eaters and grwoing the nitrite eaters. We add ammonia to feed the ammonia eating bacteria. As they grow in number thay make more and more nitrite. The nitrite eating bacteria can't start to grow until there is some nitrite to feed them so they lag behind the ammonia eaters.

How high is your nitrite? If it's at the top of the chart it is probably higher than that, and around 15 ppm it causes the cycle to stall. You can get a rough idea by mixing some tap water with tank water, roughly 1/4 tank and 3/4 tap. If this gives a reading less than 4 ppm, it's fine.

The nitrate tester works by converting nitrate into nitrite them measuring nitrite. If there's nitrite in the tank as well, that is added in and makes the nitrate reading higher than it really is, which can confuse the interpretation of where the cycle is.
 
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Beth_obrien2424

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Yes it is normal. Having nitrite fall before ammonia is unusual.

Cycling is a 2 stage process, growing the ammonia eaters and grwoing the nitrite eaters. We add ammonia to feed the ammonia eating bacteria. As they grow in number thay make more and more nitrite. The nitrite eating bacteria can't start to grow until there is some nitrite to feed them so they lag behind the ammonia eaters.

How high is your nitrite? If it's at the top of the chart it is probably higher than that, and around 15 ppm it causes the cycle to stall. You can get a rough idea by mixing some tap water with tank water, roughly 1/4 tank and 3/4 tap. If this gives a reading less than 4 ppm, it's fine.

The nitrate tester works by converting nitrate into nitrite them measuring nitrite. If there's nitrite in the tank as well, that is added in and makes the nitrate reading higher than it really is, which can confuse the interpretation of where the cycle is.
Thank you so much, this was very helpful! I didn’t know the tip of mixing tap water with the tank water to test it. That’s really interesting
 

essjay

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Testing nitrite using a tap/tank mix will only give a rough idea of the actual level as we'd need very accurate measuring equipment to do it properly, but it is good enough to show if the nitrite level has passed the stall point. If the dilution test indicates a tank nitrite of over 16 ppm, the best thing is a water change to get nitrite down below stall point and to limit the amount of ammonia added as every 1 ppm ammonia is converted to 2.7 ppm nitrite - it doesn't take much ammonia to get to stall point nitrite.
 
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Beth_obrien2424

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Testing nitrite using a tap/tank mix will only give a rough idea of the actual level as we'd need very accurate measuring equipment to do it properly, but it is good enough to show if the nitrite level has passed the stall point. If the dilution test indicates a tank nitrite of over 16 ppm, the best thing is a water change to get nitrite down below stall point and to limit the amount of ammonia added as every 1 ppm ammonia is converted to 2.7 ppm nitrite - it doesn't take much ammonia to get to stall point nitrite.
I tested the water today with the tap water and it seems to be fine. I know a cycle can take a while so I guess that’s all it is :) thank you for the advice
 
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