Bit Confused On My Cycle

cheerycherry

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Im now on week 2 of fishless cycle has been going fine until the last 3 days.On sunday ammonia was at zero so added more ammonia to bring it back up.since then my ammonia wont drop? it was dropping fine until then.

Its s 4ft x 2ft x 2ft tank 300 litres

this mornings readings are

Ammonia 7.3
Nitrite 110
Nitrate 110
Ph 7.0 usually 8.0

Havent added anything new at all? nothing has been done different at all
 
Are those readings in ppm?

For starters it seems you added too much ammonia, as you should aim to top it up to only 5ppm.
Each ppm of ammonia gets converted into 2.7 ppm of NitrIte (I think that figure is right, if not it is somewhere around there!), so you can see that you will get a lot of nitrIte created.
Your levels of NitrIte and nitrAte seem very high too, perhaps too high, although I'm sure someone else will advise if a waterchange is recommended.
The cycle does seem to move a bit then stall, move a bit then stall, I am finding the same thing with my tank that I am cycling at the moment, (currently on day 13, (well 14 today, but won't have results until tonight!), link in signature), and it has obviously processed some ammonia at some point because I have nitrItes in the tank now, but it doesn't seem to be dropping the ammonia reading anymore.
At the moment I am playing the 'sit-and-wait' game. If for me it hasn't changed in a weeks time, then I will start wondering :)
 
Ammonia over 7 is around the territory where a cycle will sometimes stall. The pH should still be alright, but in my fishless cycle, it dropped by about 1 a week or so before it dropped by about 3 more. I think a big water change is in order, and then top back up to 4-5 ppm.
 
Okay how much of a waterchange? Should I then leave it or top the ammonia back up?
 
I'd do;

50% waterchange
Leave it an hour.
Remeasure the ammonia.
If ammonia is still greater than 5ppm post back what level it is at.
If ammonia is less than 5ppm then use the calculator on this site to work out what you need to add to take it up to 5ppm, (or post the test result here along with your tank volume, and the strength (%) of the ammonia you use to add to the tank, and we'll tell you roughly how much to add :) )

EDIT: Don't forget to use dechlorinator!
 
Im not sure about nitrifying bacteria - but many bacteria have a 2 parts to their cycle.

1st part is growth and second is multiplication. So when growing, the bacteria take in nutrients (ammonia for example) and enlarge, preparing to split, and then when multiplying/splitting, they stop "feeding".

This could explain the stop/start experienced when cycling.
 

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