A few weeks into fishless cycle; My numbers:

[teamgs]

Greetings,
I am a few weeks in to a fishless cycle of my 90G tall, and was curious if these numbers are normal. BTW, adding pure ammonia, and in a day, the readings are back to 0.

pH - 7.6-7.8
Gh - 40 mg/l
Kh - 70 mg/l
NH3 - 0
NO2 - 1.6 - 2.5 mg/l
NO3 - 50-100 mg/l

I was curious as to the relatively high nitrates, yet nitrites high as well. The tank has no plants yet.

Regards,

Gary

[Zagz]

Keep dosing the ammonia and when the nitrites are 0 in 24 hours you are done. You are almost there IMO. Are you using the liquid tests or test strips?

[teamgs]

Thanks Anne!

I am using the Hagen Master Kit.

Regards,

Gary

[7Enigma]

You may be already done (depending on how much ammonia you are adding). When you say the readings are back to 0 in a day are you just talking about ammonia, or both ammonia and nitrIte?

Your high levels of nitrAtes tell me that you have already accumulated a large amount of nitrIte to nitrAte converting bacteria. It's possible you just need to do a large PWC before stocking.

I would recommend (if both ammonia and nitrIte are going to 0 in under 24hours) a large 80% PWC or so followed by a single 2ppm ammonia dosing. If you detect only nitrAte after 24 hours your good to go.

What often happens when ammonia dosing for a fishless cycle is that you build up a large amount of nitrIte in the tank. Even if you have enough nitrIte to nitrAte converting bacteria present, you have all this built up nitrIte to get converted. It falsely makes you think your cycle is still going, when in fact, you might be able to stock very shortly.

[teamgs]

Thanks guys! Just got home from a Vegas weekend, and the tank is fully cycled! Nitrites and ammonia are at 0, and nitrates are very high. I am planning to do water changes to get the nitrates down to under 40ppm, and I am also ordering my plants. As soon as the tank is planted, I will be adding the fish. (Though my 2 year old daughter is anxious to see fish right now! ) Until I get the fish, I will continue to low dose ammonia to give the bacteria a food source, and PWC to keep the nitrates down.

Regards,

Gary

[7Enigma]

Congrats on a successful fishless cycle. Few have the patience you did but you'll reap the benefits of a fully stocked tank without the trouble of PWC's!