Tank has high ammonia & nitrites

[andrewdavidd24]

So my tank has been running for over 8 weeks now. and I got it cycled around the 7th week. no signs of ammonia or nitrites. then about a week, my ammonia rose really high to about 3.7. now i am getting nitrite and nitrates again and i’m not too sure what to do. i feel like i am starting over.

 

[Aiken Drum]

Do you have fish in the tank? If so water changes are essential.

How did you cycle the tank? Fishless cycle by adding ammonia or fish in cycle?

Something must have effected your cycle. Did you add a lot of new bioload at once? Or clean out your filter? Might you have done a water change and forgotten to add water conditioner?