How Long Does The Nitrite Phase Last?

How long does the nitrite phase usually last? My nitrites have been stuck at 2ppm for awhile now. Dosing ammonia for a fishless cycle.
Here's a chart of my cycle so far:

 

It's hard to determine how long the nitrite phase will last as there are many factors that affect how long it takes to cycle.

What's the tank size, pH and temp? Are you using a bacteria supplement? After you dosed 4ml (which might have been too much) on 12/7, it appears your cycle has stalled if your nitrates went from 40 to 5. Did you do a water change? Ideally, you'd want to wait for your ammonia and nitrite to drop close to 0 before dosing more ammonia so your bacteria can catch up. And are you sure your nitrites are at 2? I know nitrites at 2-5 are hard to determine on the color chart. I'd do the dilution test by adding half tap and half tank water to the tube, test and multiply that number by 2.

 

It's hard to determine how long the nitrite phase will last as there are many factors that affect how long it takes to cycle.

What's the tank size, pH and temp? Are you using a bacteria supplement? After you dosed 4ml (which might have been too much) on 12/7, it appears your cycle has stalled if your nitrates went from 40 to 5. Did you do a water change? Ideally, you'd want to wait for your ammonia and nitrite to drop close to 0 before dosing more ammonia so your bacteria can catch up. And are you sure your nitrites are at 2? I know nitrites at 2-5 are hard to determine on the color chart. I'd do the dilution test by adding half tap and half tank water to the tube, test and multiply that number by 2.

Tank is 2.6G, pH 6.4, Temp 78-80F
No bacteria supplement
1 gallon water change done on 12/4, 90% done on 12/2
Nitrates could be 5, really hard to read, think it's been 2
I'll try the 1/2 water trick and do a large water change tomorrow, probably 90%.

 

I would do a 75% water change to drop the Nitrites down. Looks like you have stalled a bit. It can happen with Nitrites over 2ppm. You may have to do water changes everyday at this point to keep the Nitrites below 2. Without bottled bacteria, this point can go on for a couple of weeks actually. Sorry to say. This is the longest part of cycling.

Are you using the dosing calculator to dose your ammonia? 1ml of ammonia isn’t the same as 1ppm of ammonia.



With that small of a tank 1ppm is plenty of ammonia.

Do a 75% water change
Dose 1ppm ammonia
Recheck parameters in 24 hours

Expect to do water change before next dose of ammonia also. Once your Nitrites drop on their own without the water change, then you can stop and dose the ammonia on its own.

 

I can't figure out that dosing calendar, tried before. I'll test my water to see how much I dosed today. I thought the goal was 2ppm per day?

 

In this small of a tank, I'd only dose to .50ppm. What is your stocking plan for it? Do you have any other established tanks you could take the media from? If so, you wouldn't need to go through a fishless cycle.

 

Stocking to be determined at this point. Probably a shrimp only tank. No media to spare so that's out of the question. Just have to wait this whole cycle thing out. No hurries.
So you think dose to .50 ammonia is good? I can do that. I added 5ml today to see how far it drops tomorrow, then a big water change. So far the water changes aren't lowering the nitrites any lower than 2ppm. Check the tap water several times and no nitrites in it so it's definitely a tank issue. Wonder if my substrate is affecting it? Fluval stratum does affect pH. May be a contributing factor? I've thought of capping it a little with river rocks.

 

The goal for a cycled tank, no matter what size, is to convert 1ppm of ammonia to nitrates in 24 hours. You increase the ammonia dose, with bigger tanks that have larger stocking.

I think this is why you are stalling. 2ppm of Ammonia is too much for that small of a tank. So it is raising your nitrites too high.

Do a 100% water change before you dose your ammonia the next time.

 

For a shrimp tank, you barely need .50 dosed, IMO. They have a very insignificant bioload. You honestly don't need much seeded media to jump start this tank. A small section of sponge or a couple of ceramic rings depending on what you have in your other tanks would be plenty!

 

Today's readings:
Ammonia 2ppm
Nitrite 1-2 ppm (hard to tell)
Nitrate 5 ppm
Temp 80F

Did 2 gallon water change with Prime. Will retest tomorrow.

 

That is progress for sure! Drop in Nitrites and + nitrates. Won’t be long now!

 

Well, the drop in levels are due to the near 100% water change. And if you did that, I'm puzzled as to why your ammonia is at 2. Did you dose more ammonia after the water change?

 

Readings were before the water change and I dosed last night. I haven't tested after the water change as it hasn't been 24 hours since adding Prime.

 

You don't need to wait 24 hours to test. Prime doesn't affect the readings.

 

I'll have to go test again, see where I'm at now. I didn't dose ammonia today, just Thrive S.

After 2 gallon PWC from this AM.
Ammonia 0
Nitrites 1-2ppm (still)
Nitrates 5 ppm
pH 6.8
Temp 80F

New chart, added PWC column.

 

Can you increase the temp to 84F? If not, that's fine. Don't add any more ammonia and don't do a water change, just re-test in 24 hours. You want to see that nitrite drop on its own.

 

Will do, thanks! I tested my other tank and the tap water again, no nitrates in either. Thought maybe my test was broken. Nope, just have high nitrites right now. The purple color is really hard to read. When should I change more water? When should I dose ammonia again? Thank you!

 

Once your nitrite drops to .25, you can then re-dose but again, I'd only dose to .50ppm for this tank size. Your goal is to allow the bacteria to develop and process the ammonia and nitrite on its own without having to intervene with a water change. If you don't see your nitrite drop to .25 in a couple of days, I'd add in a very tiny pinch of fish food. This will accomplish two things - 1. provide a food source for your ammonia processing bacteria (since it's been at 0 for some time) and 2. help convert nitrites as sometimes our tap water doesn't have enough phosphates which is helpful in lowering those levels.

 

So far no drop in nitites, still 2ppm.

 

Can you do the dilution test on nitrites by taking half tank and half tap, test and multiply that number by two? Just asking because 2 and 5 on the chart is hard to tell and you want to be sure what your levels are.

 

Just sounds like you don't have enough nitrifying bacteria to turn the nitrites into nitrates. You can help it out by manually removing the nitrites with daily 25% water changes. However, it looks as if your tank is nearly cycled

 

Can you do the dilution test on nitrites by taking half tank and half tap, test and multiply that number by two? Just asking because 2 and 5 on the chart is hard to tell and you want to be sure what your levels are.

Did the diluted test and it came out 2ppm. So my nitrites are at 4ppm not 5ppm. Do I add more ammonia? Water change? I'm not sure my next step.

OK, did a .50g PWC. Tested nitrites again, this time it came down to 2ppm. Added 2ml of ammonia to see what happens next.

Today I changed 2 gallons of water. Tested again and got
Ammonia 0
Nitrite 2 (did dilute test as well and got same results)
Nitrate 10

Why are my nitrites not going down with water changes?

 

I would not have added more ammonia when your nitrites didn't come down from 2 before. This is why despite the water change, your nitrite went back up. Don't dose anymore and don't do a water change (unless they stay at 4-5 for a couple of days). You want to wait until your nitrites drop by themselves to .25 before dosing again or else you just get into this cycle of doing unnecessary water changes without allowing the bacteria to develop and process those nitrites on their own.

 

Sounds good, I'll leave alone for a few days and keep testing.

Leaving alone did the trick. Came home tonight to ammonia 0, nitrite 0, nitrates 5. Used 2 different test kits.




Would you say the nitrates (in pink) is more like 10? When I did the dilute test on the API kit it showed 5 so double is 10. In the photo it appears red, not in true life. So my nitrates are between 5-10. Still, NO nitrites. Yes!!

 

You seem cycled at this point. But if you haven’t done ammonia in a couple of days, I would add ammonia now. You still need to feed your bacteria. I would add ammonia up to 24 hours before adding fish. This will also help you confirm your cycle. If you keep dropping from 2ppm to 0 Ammonia in 24 hours for a couple days in a row, then you are cycled for sure.

It isn’t important to be exact with nitrates. As long as you stay below 20 in a non-planted tank, you are good. I would read the pink one as 7.5. Definitely between 5-10

 

So dose the tank with ammonia and retest tomorrow?? I'm confused.

 

Great news on the ammonia/nitrites going down. I'd go ahead and dose to .50 ammonia and re-test tomorrow. If the ammonia/nitrite drop to 0 within 24 hours, you're cycled. Just make sure to do a large water change before you add the shrimp.

 

Today's readings, no ammonia or nitrites. Using an API and Fluval test kit.
Ammonia 0
Nitrite 0
Nitrates 5
pH (2 different readings per test, 5.5 or 6.8)
KH 0-.50 ppm (3 drops)
GH 100-200 ppm (6 drops)
temp (using a digital probe) 78.5F

History, started with HOB filter in 1.5g tank on 11/14/2017. Moved filter media over to Fluval tank's media on 11/24/17. Started dosing ammonia on 11/29/17 after using fish food up until then. Mind you the ammonia was very high in the original tank. Think I'm done? Now ammonia is converting to 0 after 24 hours and no nitrites. Could it be cycled in one month already?

 

I would say you’re cycled. One month is about average. My first tank took 5 weeks.

 

So dose the tank with ammonia and retest tomorrow?? I'm confused.

Keep dosing ammonia until the day before you add fish. Your bacteria still needs food. Ammonia is bacteria food. If you stop feeding them, they will die within a couple of days.

I always do a large water change the morning I add fish. That way the nitrates are as low as you can get them, before fish are added. Nice clean fresh water for your fish.

 

So I think I'm cycled and added one nerite snail. I've ordered some ghost shrimp and they should be here next week. With the nerite in the tank will that be enough ammonia for the BB? I know it's early for the snail, but I have algae and for $3.99 I took the chance.

 

I doubt one nerite will sustain the amount of ammonia you were processing. You were going to make this primarily a shrimp tank?

 

Yes, shrimp and 1 snail only. No fish.

 

Shrimp have less bioload than snails. I think you should be ok with your cycle.

 

Thanks for all your help and advice. I will continue to monitor my parameters daily and if needed be prepared to add in ammonia again. This is so exciting to be finally cycled.

 

Sure but don’t add any pure ammonia now that you have the snail.

 

Sure but don’t add any pure ammonia now that you have the snail.

I won't. I have a back up plan if the cycle goes haywire and I have to start adding again.

Added 7 ghost shrimp to the tank, didn't realize they were so big. Will test tank tomorrow with the increase in bioload with life in the tank. So far ammonia 0, nitrates 0, nitrates 5 since 12/15/17.

Here's my whole cycle chart for those interested: