Ammonia Spike Without Adding Anything – Cycle Day 16

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msaleh26

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Hi everyone,


I’m on day 16 of my cycle and seeing something strange.





  • First ammonia dose: 2 ppm → 0 ppm in 24 hrs
  • Second ammonia dose: 2 ppm → 0.5 ppm in about 1 week
  • Then, without adding any chemicals or food, ammonia spiked back up to 2 ppm
  • pH steady around 8.0
  • Return pump + 2 powerheads running 24/7
  • 30 lbs sterilized rock + 20 lbs live CaribSea
  • Sand is completely sterilized
  • Water was hazy for 10 days, now clear
  • Diatoms appeared in week 2
  • I’ve scraped biofilm off the glass
  • Nitrite and nitrate are still zero
  • Dosed 12 oz of Dr. Tim’s One & Only on day 1







Is it normal for ammonia to spike again like this without adding a source? Could the live rock or biofilm be releasing something back into the water? Any advice on whether this is a stall or just a weird phase?





Thanks!
 
I got a used Red Sea system, I bleached the rock and the sand and rinse a lot of time with rodi, and prime to dechlorine the rock and the sand
 
https://www.reef2reef.com/threads/does-prime-actually-detoxify-free-ammonia-nh3.849985/
Prime. It seems to interfere with cycling tests. Did it cause your results, or hide the uncycled tank for awhile? I don't know but it seems to be a common factor in interesting test results.

The cloudiness you mentioned is often presumptively a bacteria bloom in early cycle tanks. That the ammonia "came back" is a mystery. Do you have anyone "helping" with the process?
 
So I used the prime after I bleached the rock and the sand, I haven’t used the prime on the current water that I am trying to cycle, I used rodi for that.
After the bleaching I air dry it and rinse it very will for both the sand and the rock.
I watched Video on you tube on how to safely do it with 1:10 bleach to water ratio. I haven’t had any other help from anyone.
What I am trying to know, is what I am seeing normal? Nitrite still 0 on day number 16?
 
I'm easily confused....... what are the ammonia-nitrite-nitrate readings today on day 16?
 
Sorry for the confusion,
The ammonia is reading at 2 on day 16, nitrite is still 0, nitrate is 0.
Could you please check my initial post again and let me know if what I am experiencing is normal? Especially the ammonia spike and the nitrite reading?
 
According to the parameters today the tank is not cycled, its very strange. Its still early morning here, others more knowledgeable and experienced than I should be able to offer some advice. Good luck
 
Bleaching will kill organisms, but only very strong bleach for an extended period will remove organics. Without doing that, there may be organics on the rocks that are now breaking down, leaving ammonia.

I do not know if the 2 ppm is real or a test error, but if it were me, I’d add Fritz turbo start now. If it is not adequately cycled now, it will be after doing that.
 
Bleaching will kill organisms, but only very strong bleach for an extended period will remove organics. Without doing that, there may be organics on the rocks that are now breaking down, leaving ammonia.

I do not know if the 2 ppm is real or a test error, but if it were me, I’d add Fritz turbo start now. If it is not adequately cycled now, it will be after doing that.
I added the fritzyme as you advised and that’s product is amazing, ammonia was 0 the next day and nitrate showed up as well, it’s been 2 week since I added the fritzyme, the nitrite still around 5ppm, and the nitrate is about 80 today, should I just do a water change and start adding livestocks?
I added 0.5 ppm ammonia last Saturday and I added 0.25 yesterday to feed the first group of bacteria, it was 0 the next day when I added the 0.5, I haven’t tested today yet.

Should I try to do add 2 ppm ammonia to make sure it goes in 24 hours?

Thanks.
 

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