Fishless Cycle

[yabadaba]

Hi guys, I started my fishless cycle 9 days ago, using a little mature media from my other tank and finally yesterday (the 8th day) the ammonia level fell to 1ppm, so I tested for nitrite, nitrate and ph, too. Here are all the results:

Ammonia = 1ppm
Nitrite = 5ppm (maybe off the scale?)
Nitrate = 20ppm
pH = 8

Just wondered if this is looking as expected (from what I've read it appears to) and how long I can expect to wait for the nitrite spike to end? Also, just to confirm, should I wait until the ammonia actually drops right to zero before I start adding more ammonia?

 

[OldMan47]

With a minor jump start, I would have expected better progress by now. You have started to move into a nitrite spike now so expect a while of off scale nitrite readings while the ammonia continues to improve its performance.

 

[yabadaba]

With a minor jump start, I would have expected better progress by now. You have started to move into a nitrite spike now so expect a while of off scale nitrite readings while the ammonia continues to improve its performance.

Yes, I was expecting something to happen quicker than it did, though maybe it's because I was limited in how much of the media from my other filter I could transfer across. It's a Fluval U3 internal and even though I transferred about half of the Biomax to the new filter it looked a pitifully small amount when mixed in with the media that came with my new Eheim 2080.

The one thing that has surprised me a little is that nitrate is now showing as being present, where there was none before. I thought that only appears as a by-product of the nitrite eventually being consumed and therefore it wouldn't show up until the nitrite level starts dropping.

 

[waterdrop]

With a minor jump start, I would have expected better progress by now. You have started to move into a nitrite spike now so expect a while of off scale nitrite readings while the ammonia continues to improve its performance.

Yes, I was expecting something to happen quicker than it did, though maybe it's because I was limited in how much of the media from my other filter I could transfer across. It's a Fluval U3 internal and even though I transferred about half of the Biomax to the new filter it looked a pitifully small amount when mixed in with the media that came with my new Eheim 2080.

The one thing that has surprised me a little is that nitrate is now showing as being present, where there was none before. I thought that only appears as a by-product of the nitrite eventually being consumed and therefore it wouldn't show up until the nitrite level starts dropping.

No, it makes sense that you sometimes begin to see some nitrate(NO3) despite not yet having gone through the various "phases" of cycling feedback results yet. Its important to always remember that cycling is not a chemistry experiment, instead it falls within the realm of biology. You may be starting with a tiny number of bacterial cells of both A-Bacs and N-Bacs, but those few cells are alive and will be "doing their thing." So there will, right from the beginning, be some ammonia getting converted to nitrite and then to nitrate. This will begin to build up the nitrate, potentially to a point where our nitrate test can actually "see" it, despite that fact that perhaps our nitrite(NO2) test can't actually "see" enough of the small amount of nitrite "passing through" to be able to "show" it yet. Does that makes sense? Our tests can't detect what's going on down at lower levels. Even though .025ppm, at a "quarter of a part per million" sounds very low and sensitive... its nothing compared to how small the bacterial cells and molecules of ammonia and nitrite and nitrate are. In a sense there has to be "gobs" of activity going on on the molecular scale before we and our tests see it up in our world!

~~waterdrop~~

 

[yabadaba]

Thanks for that explanation waterdrop, what you said makes perfect sense.

 

[OldMan47]

Another factor that enters into the equation, when you use WD's explanation, is that each 1 ppm small change of ammonia can produce about 3.6 ppm of nitrate. That means that sometimes it is easier to see the nitrate move than it is to see the ammonia end of things.

 

[waterdrop]

Another factor that enters into the equation, when you use WD's explanation, is that each 1 ppm small change of ammonia can produce about 3.6 ppm of nitrate. That means that sometimes it is easier to see the nitrate move than it is to see the ammonia end of things.

Yes, completely true, forgot to add that. OM, do you actually remember that its 1 to 3.6, ammonia to nitrate, or is it 1 to 2.7 ammonia to nitrite and then 1 to 3.6, nitrite to nitrate? I thought once that you and I agreed we couldn't remember which it was, lol. WD

 

[OldMan47]

I'm pretty sure the 2.7 is ammonia to nitrite. The hitrite to nitrate is not a huge ratio but does increase again with the extra oxygen.

 

[yabadaba]

Okay, the ammonia reading dropped to zero so I added another 15ml about 14hrs ago and that raised the level back up to about 3ppm and in that period of time it's reduced again to 0.25, which I guess is what I would want to see happen. My nitrite reading is now at 5ppm (or possibly off the scale) and I'll be checking this daily from now on.

But, literally overnight my lovely clean sand and filter pipes have become covered in a thin layer of algae, some brown and some green. The sand surface looks almost as if patches of it are stained - took me a while to figure out what it was! As there are no fish in the tank and originally no sign of algae I was leaving the tank lights on for about 14hrs or so a day to help the plants I have in there, but I'll reduce that now to about 6-7hrs daily. Also I was dosing weekly with Tropica Plant Nutrition + but will stop that in case that is making the algae problem worse.

So far I haven't disturbed the sand since setting the tank up, so I'm thinking that maybe just turning the sand over a little on a regular basis, will remedy that part of my algae problem?

 

[OldMan47]

It sounds like you are making some nice progress on cycling now.

 

[waterdrop]

Yes, sounds like you got the light "backwards" but have now moved in the right direction. What I've learned from some of the serious plant hobbyists is that sometimes they start off with as little as 4 hours of light per day when the tank is brand new because the plants will not yet have settled in and quite started to grow strongly. They then gradually (I don't know at what rate or exactly what symptoms they use for feedback) increase the daily hours to 6, potentially stopping there or moving on toward 8 or possibly even more if they have no algae yet.

Algae is a result of ammonia and light and fishless cycling certainly provides plenty of the former!

~~waterdrop~~