Fishless Cycling

[sj ponder]

Oh, I forgot to mention that our latest ammonia reading seems to indicate that it's dropped slightly below 4ppm. We have to "interpolate" between 2ppm and 4ppm on the color chart. My son is calling it 3.7 Once it start dropping, I wonder how fast we should expect it to drop...

 

[rdd1952]

The water change usually seems to jump start the process again. I'm not certain why this is but it usually does. After you do it, I wouldn't add any more ammonia until it does drop back to zero (or close to zero). Just test to see what the reading is so you can monitor any subsequent change. The fact that you have a slight amount of nitrite indicates that some ammonia has been processed (any nitrate yet).

As for the temperature, that could be the reason things are going slowly. Most bacteria multiply at very fast rates but nitrifying bacteria are extremely slow to multiply. It takes the ammonia oxidizing bacteria between 7 and 30 hours to double just once (nitrite oxidizing bacteria are slower). The optimal pH range for reproduction is between 7 and 8 and reproduction is much faster at higher temperatures. So getting the temp to the upper 80s could cut the reproduction time by quite a bit.

As I mentioned, pH also plays a factor and I forgot to ask in my previous post what your pH was. As the pH gets lower, reproduction slows and can actually stop as the pH drops to 6 or below so if your pH is in the low 6s, that is also slowing the process.

Edit: Those charts are hard to differentiate. I know what you mean on the color difference. And the nitrate one is the worst. I can't tell the difference in anything over about 20 ppm.

 

[sj ponder]

After being away for several days, we tested our water for the first time in 3 days, and voila - the ammonia reading was near zero! It has been exactly 2 wks since we started. Just prior to testing the water, we had made a trip to the local fish store to obtain some gravel from one of their tanks, to try to jump start the process. Well, we're not going to use that now.

We added 2mls of ammonia to take it back up to 2-3ppm...

Oh, the nitrite was reading at about the top of the chart - about 10ppm.

 

[shelaghfishface]

fab info on fishless cycling,shame i didnt read it before i started
well done

 

[sj ponder]

22 days since we started, and we're having some problems...with chlorine?!

Things were going well. Ammonia would drop to zero in 12hrs each time it was added.
Nitrate at >10ppm and Nitrite at >200ppm were both off the chart, but not unexpected.
Then we started seeing Chlorine...where did that come from. My son added some water,
but also added Novaqua+ conditioner for dechlor. Yet we're still seeing chlorine at 1-2ppm.

Ammonia still was down to zero this morning, but this evening, 13hrs after he added ammonia
this morning, the ammonia level is still 3-4ppm. Even though the ammonia-eating bacteria
is around, it doesn't seem like it is doing as well as it was 1 week ago.

Where the chlorine is coming from is a real mystery. Is it possible to overdose a tank with
Novaqua Plus?

 

[rdd1952]

What type test kit are you using. Strips can be very inaccurate. I haven't seen test kit that would measure nitrite and nitrate that high but you may have a different type liquid kit from mine. I'm unsure why you are seeing chlorine but depending on how long after you added the water and dechor it was before you tested, it could be from the chloramine being broken down, producing chlorine and ammonia.

 

[sj ponder]

For ammonia, we have a liquid API kit. For the other readings (nitrate, nitrite, chlorine, ph, gH, kH), it is a test strip. It's strange because we were used to seeing results with chorine at zero. I had my son take a gallon of tap water, measure the chlorine, add Novaqua+ and measure again - just to make sure the test kit and Novaqua+ are working OK. He was able to see chlorine for the initial reading, but still saw 0.5ppm chlorine after adding the Novaqua+. The Novaqua+ says to shake thoroughly before using, and apparently he wasn't doing that. After shaking thoroughly, and adding, he was able to get the chlorine reading to zero on the small water sample.

So he added more Novaqua+ (10ml to the 20gal tank). Read the chlorine about 30min afterwards, and still seeing 1ppm chlorine. We've also done the test long after water and dechlor have been added and seen chlorine.

What type test kit are you using. Strips can be very inaccurate. I haven't seen test kit that would measure nitrite and nitrate that high but you may have a different type liquid kit from mine. I'm unsure why you are seeing chlorine but depending on how long after you added the water and dechor it was before you tested, it could be from the chloramine being broken down, producing chlorine and ammonia.

 

[rdd1952]

I would trash the strips. I have never had any faith in them as they are extremely inaccurate. I definitely can't explain why there would still be chlorine showing in your tank though. The dechlor you are using should handle both chlorine and chloramine and after about 24 to 48 hours, all chlorine should be disipated from the tank even if the dechlor didn't remove it.

 

[sj ponder]

Well, the ammonia is still being processed, so we'll ignore the chlorine readings for now. Should we consider a water change? I'm wondering if the nitrite level might be too high.

 

[rdd1952]

It certainly won't hurt to do a water change. Some people believe that it slows the process but in actuallity, lowering the levels in the tank actually speeds it slightly. At least you would have nitrite down to where you can see what it is.

 

[sj ponder]

Seeing the light at the end of the tunnel. It's been about 5wks since we started. Have not been that diligent about taking readings, but yesterday nitrites were down to zero! We did a 95% water change last weekend. There were still some nitrite/nitrate readings afterwards. Added ammonia a few times since then. Yesterday, ammonia was added after getting the zero ammonia and nitrite reading, to take the tank back up to about 3ppm ammonia. 24hrs later, ammonia is back to zero, but we're getting a nitrite reading. Maybe 5ppm?

We were just going to go ahead and try to add a couple of fish after a water change today, but after we went to the LFS, my son decided to wait a little longer before adding fish.

 

[rdd1952]

Still having 5 ppm of nitrite 24 hours after adding ammonia is concerning. It would appear that none has been processed. Did the nitrate go up any in that time frame. How often did you add ammonia after the big water change last weekend?

 

[Mark123]

Very helpful info!

I started by adding the required amount of ammonia 4 days ago and already my ammonia reading is 0 & nitrites are 0. Nitrates are very high though. Have added enough ammonia again to get it up to 3-4 ppm.

the ammonia seems to have been processed very fast! Is this right?

The Coral gravel was all from a tank which previosly housed my goldfish. I suppose this would of helped?

 

[rdd1952]

Gravel from an established tank usually doesn't hae much of an effect as the gravel doesn't contain a large amount of bacteria unless the tank has an under gravel filter. Did you only add ammonia once in the first 4 days? What are the readings on nitrate for your tap water? It would be odd that you would see high nitrate from only 4 ppm of ammonia. My understanding is that ammonia to nitrite to nitrate is pretty equal so 4 ppm of ammonia would have an end result of 4 ppm of nitrate.

Also, what type media do you have in your filter? Carbon can sometimes absord the original ammonia until it becomes saturated. Other medias such as nitro-zorb and zeolite can also adsorb ammonia so that it is not processed.

 

[bangit]

Need some advice please!

Ive had a juwel rekord 96 (approx 96 litre volume) set up and fishless cycling for 11 days now.

the heater is on to the low 80s. I havent added any media to the tank containing bacteria. (from lfs etc) - assumed it wouldnt make a massive difference.

I added 5ml of pure ammonia on day 1.

My readings are still high for ammonia 4mg/l and low for nitrite <0.3 mg/l.

Im assuming im still in the "waiting for the nitrite spike" phase. I completed a fishless cycle about a year ago on an old tank and it only took about 2 weeks so could anyone advise me on why this seems to be taking a lot longer (i no longer have the old tank so cant add any media from it)

thanks