Fishless cycle questions

abcdefghi

abcdefghi

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Jun 6, 2007
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I think I am almost at the end of my fishless cycle, my nitrites spiked for about a week (drops turned instantly purple on the API kit before I even had a chance to shake the tube) and the nitrites have now dropped to 0. My nitrates are increasing (can't remember the number, but its getting dark red on the API kit).

But, my ammonia has never gotten below 0.5ppm. Now, I know this is because as soon as I see the ammonia is getting low I dose it back up again to about 1-2ppm. But how much longer after nitrite is back at 0 shoud it take for ammonia to start hitting 0 in 24 hours?
 
you want to dose the ammonia to 5 ppm and see it reduce to 0 over 25 hours to consider the cycle complete. time it takes seems to vary greatly but the slowest part of the cycle to establish is the Nitrate production so you're nearly there.

how big is the tank and what are you going to stock ? possible you have established sufficient bacteria to go for it, if you are reducing 2 ppm Ammonia to 0 with no nitrites.
 
The tank is a 55G, I plan to initially stock with 20 glowlight tetras (and if I can find them 3 pearl gourami, but may add those at a later date once the glowlights are settled) and will eventually add about 10 cories.

I should add its not made it to 0 yet as I always add once it gets low. The lowest it has gotten so far has been 0.25-0.5ppm. I am fine with waiting, just not sure how much longer this part of the cycle will take now that my nitrites have gone back to 0.
 
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You need to let it drop for 24 hours and see if its doing it or not. If not, go ahead and dose it back up. If it is getting to 0 that fast, give it one more try just to make sure before you go looking for fish.
 
Thanks, I dosed some ammonia at about 7pm yesterday so will check things tonight and see where they are. I think my main worry is that my nitrite has now hit 0, while I thought that the ammonia and nitrite would hit 0 at about the same time.

I had hoped to finally get fish this week, cycle has taken about 6 weeks so far. The waiting is not bothering me too much, and I would prefer to wait rather than risk killing any fish I do get.
 
I think I will just stock with the glowlights first, then wait a few weeks to be sure everything is settled and then add the pearl gourami (if I can find them) and lastly add the cories 3 at a time.
 
The bacteria colonies don't establish all at the same time. since you're dosing ammonia and not nitrite, the ammonia-eating bacteria build up a colony first. They start producing nitrite, so the nitrite-eating bacteria then have a food source and start colonizing. By the time your nitrite spikes up high, your ammonia levels should reduce fairly quickly when you dose the tank. This is because the ammonia-eating bacteria have already established but the nitrite-eating bacteria have not. In any case, it sounds like you're doing it right and are nearing the end.
 
sploke said:
The bacteria colonies don't establish all at the same time. since you're dosing ammonia and not nitrite, the ammonia-eating bacteria build up a colony first. They start producing nitrite, so the nitrite-eating bacteria then have a food source and start colonizing. By the time your nitrite spikes up high, your ammonia levels should reduce fairly quickly when you dose the tank. This is because the ammonia-eating bacteria have already established but the nitrite-eating bacteria have not. In any case, it sounds like you're doing it right and are nearing the end.
Click to expand...

I think that is what is confusing me, my nitrite has spiked and gone back to 0, but my ammonia has not yet hit 0, it goes down, but not yet to 0. Fingers crossed only another week or two and I should be done.
 
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