Cycle Over Slight Amount Of Nitrite No Nitrate

[nicko@rotherham]

hi all i think my tank has finishied its cycle it now reads after ba month of waiting and cycling with a hand full of fish that are still alive ph 7.0 no ammonia nitrite only slight and there are no nitrates can i add more fish now and the other thing that worries me is my plants arnt growing as fast as they have been is this because there using up all the nitrate in the tank do i need to add npk to help but not sure if i will be doin harm than good? . thinking about getting a dwarf plec any no a good one that doesent grow more than 4-5 inch many thanx people.

 

[OldMan47]

Very low nitrites is not a fully cycled tank but one that may be getting close to being cycled. It may be that your plants are removing much of the nitrogen before it is converted to nitrates, which would explain the low nitrite values with no measurable nitrates. Plants will preferentially use ammonia before using nitrites or nitrates so they may be one of the things keeping your fish alive in an uncycled tank. I would wait until you see no ammonia or nitrites a full week after the last water change before assuming that you have a cycled tank, that is not where you are yet.
Using NPK in a tank needs to be evaluated with the lighting and CO2 needs of the plants in mind. I have a tank that runs with pressurized CO2 and uses bright lights to grow plants. That tank is the only one that I dose with NPK additives. I also use a trace element mix in that tank. Unless you are ready to try the full spectrum of caring for a high tech planted tank, it is often better to just accept the slower growth that you will get with the plants using up the nitrogen and other chemicals that are introduced using fish food and water changes.

 

[mattlee]

if your using the API master test kit to test mitrates then make sure you give the second bottle a really good shake to mix the contents up well otherwise it will give false readings. this may be why you are getting 0 readings on your nitrate test