Nitrite not going down - fishless cycle

[ranicrab]

Hi! We started the cycle on 5/20 with janitor ammonia (20 gallon tank). We have plants and a couple of pond snail stowaways. The first nitrites appeared on 6/18. The last week of tests have been (all API tests)

0 ppm ammonia (have been adding 1/4 tsp daily to bring to 2 ppm)
5 ppm (or more) nitrite
5 ppm nitrate.

We had a few tests that maybe the vial wasn't shaken vigorously enough (1 reading at 60 ppm, the rest have been mostly 5, maybe 10...API tests

So, are we on track or is there something else we could do? Our ph meter showed 7.8 but we may need to calibrate...ok, thanks!

 

[tangs27]

I would recheck the levels and then dose the ammonia to 4ppm and then retest 24 hrs later there should be a change in nitrites.

Another option is a water change in case the cycle stalled.

 

[Britty]

If your first stage bacteria are established and are removing 2ppm ammo every day then adding full ammonia doses every day while nitrites are off the chart just keeps making more nitrite which keeps compounding and can then lead to a stall.

Do 50% water changes until your nitrites measure visibly less than 5ppm on the API test. As many as it takes. It wont hurt the cycle. Remember dechlorinator for the water changes.

You can then ammonia dose the 2ppm every second day as the first stage bb are established and you just keep them alive now while the second stage bb for nitrite to nitrate conversion get a foothold

 

[ranicrab]

Thanks! We will try the water change route since it does seem to be a stalled cycle....

 

[Mebbid]

Thanks! We will try the water change route since it does seem to be a stalled cycle....

It's unlikely that it's stalled but I do agree with the water changes. Don't worry about 50% changes but instead just do a solid 90% change. It won't hurt anything. The bacteria that consumes nitrite does take quite a long time to grow so it's not unexpected what you're seeing.

Stalling generally only happens because of a lack of nutrients in the water rather than too much nitrite or nitrate. Try adding some fish flakes a couple times a week to the tank to provide them.

 

[ranicrab]

Well, we didn't add ammonia for 1 day and haven't changed the water yet, but now nitrites are at zero! We are going to do 1 more check to see if both go to zero after adding 3-4ppm - then maybe we can get some fish!! Wow, it will be so strange to see something moving around in there!

 

[Britty]

Well, we didn't add ammonia for 1 day and haven't changed the water yet, but now nitrites are at zero! We are going to do 1 more check to see if both go to zero after adding 3-4ppm - then maybe we can get some fish!! Wow, it will be so strange to see something moving around in there!

Nice. If your final test works out all zero then you will still need to do a large water change afterwards to remove the accumulated nitrates. But after that, enjoy getting those fish!