I only have a NO2 and a NO3 kit; I have just bought an ammonia one online to check that too.
So I did a test.
50% change, left it one week. NO2 and NO3 both at zero
Left it another week; NO2 at zero, NO3 very very red.
I didn't think I was over stocked. I have a 4x2x2 tank.
In it are:
1x Very Large Pleco
1x Quite Large Green Terror
1x VL Clown Loach
1x QL Clown Loach
1x Large Clown Loach
2x Large Silver Dollars
1x Spotted Catfish
So I did a test.
50% change, left it one week. NO2 and NO3 both at zero
Left it another week; NO2 at zero, NO3 very very red.
I didn't think I was over stocked. I have a 4x2x2 tank.
In it are:
1x Very Large Pleco
1x Quite Large Green Terror
1x VL Clown Loach
1x QL Clown Loach
1x Large Clown Loach
2x Large Silver Dollars
1x Spotted Catfish