When to stop Ammonia

[gamma_draconis]

I'm in the middle of a lengthy fishless cycle and was wondering if maybe I'm not doing everything quite right. I am using pure NH4 and dosing to about 3.0 ppm (or trying to at any rate). I started noticing nitrItes about 2 weeks ago and nitrAtes a few days later. I thought I wasn't supposed to let the NH4 get under 1.0 ppm but wouldn't that just keep perpetuating the cycle? When do I know it's okay to stop dosing and let NH4 go to zero?

My last two readings were as follows:

May 26th:
NH4 - 2.0 ppm
NO2 - 1.0 ppm
NO3 - 30 ppm

May 28th:
NH4 - 2.0 ppm
NO2 - 0.50 ppm
NO3 - 60 ppm

Should I stop adding ammonia so that I can get NH4 and NO2 down to zero and call it cycled?

 

[Sidi]

It sounds like you're well cycled. So basically you want to stop adding ammonia, do a massive water change (most to all of the water), and add fish. You could take several days after stopping ammonia and adding fish to clear the ammonia, but you can't wait long between the ammonia additions and fish or the bacteria will die off.

It's the massive water change that's really the key, that's what will drop the ammonia to a safe level. Also, don't just add a couple fish, wait a few weeks, and add a ton of fish. You should be cycled to stock the tank pretty well now, Test of course, but the bacteria will reduce to the stocking level before long.

 

[Fishyfanatic]

Your tank is cycled when you dose ammonia and 24 hours later you have 0 Ammonia and 0 Nitrites. Since you have Nitrites present, half the daily Ammonia dosage. After the tank is cycled, do a large water change (90%) then add fish. I wouldn't wait because the bacteria could die off.

 

[neilanh]

Agreed, you're almost there, just not quite. Keep feeding the ammonia until, like FF said, you can process through in 24 hours. Then you'll be ready for a massive PWC to get the nitrates down, and add fish.

 

[Sidi]

Doh, didn't read the results closely enough last night (beer, the solution to, and cause of, all of life's problems), thought they were at 0 now. Yeah, as said above wait for the nitrites to drop then do your change. It won't take long at all now, probably a few days.