ammonia high nitrites low and nitrates in midrange??

What kind of fish are you keeping and how many?
how often do you do water changes?

Is the tank fully cycled?
Did it get thrown into a mini cycle some how?
 
i havre like 20 fish..i am probly in mid cycle range right now i do a 10 gallon water change everyweek and a 2.5 every other day
 
Hmmm, what size is the tank?
20 of what kind of fish?

You could be over-stocked and your Bio-load is to high for the bacteria to keep up with.
 
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