Cycle Readings

[wingfeet]

hi all

I started my new tank on Saturday adding ammonia for fishless cycle.

I have just done my first test and it as follows---- Ammonia-4.0ppm
Nitrite-5.0ppm

My question is do I test every day now until I get the desired readings of -.75 ammonia and nitrite over 2ppm.

Thanks

Scotty

 

[Gruntle]

It's probably best to wait three days between testings at this point. Mostly because your bacteria colonies are small (only just started) there won't be a massive change in daily levels, and as a result you won't see a major change and you'll be using up your test kit for no good reason.

The key is not to add any more ammonia until you get the magical "less than 0.75ppm ammonia AND more than 2ppm nitrite." I've read here quite often that people have topped up their ammonia levels back to the 3ppm (4ppm is an older measure from previous cycles, over many years of experimentation it has been determined by people far smarter than me that 3ppm is more than sufficient). Adding more ammonia just adds more nitrite (the nitrite processing bacteria colony grows about 1/3 as quickly as the ammonia processing bacteria, so more ammonia can stall your cycle due to far too much nitrite).

Once you get your 0.75ppm/2ppm reading and add your second dose of ammonia, you can move to every second day testing.

 

[wingfeet]

I'm two weeks into the cycle now.

I'm testing every day and topping up Ammonia to 3.00ppm as it drops every day while nitrite is still high. I have nitrates showing in the tests.

When would you think nitrites start dropping?

Regards

Scotty

 

[Essjay]

Stop adding ammonia!


You should not add ammonia whenever it drops to zero, that is an old way of fishless cycling and it makes so much nitrite the cycle is likely to stall.

With the method on here, you add 3 ppm ammonia, then test every third day till ammonia is below 0.75 and nitrite is above 2.0
Then you add a second 3 ppm dose of ammonia and start testing every second day. You are waiting for the day when you have had zero ammonia, then have zero ammonia again two days later. At this point, you add just 1 ppm ammonia and keep testing until you reach a day when ammonia is less than 0.25 AND nitrite is below 1.0. Then and only then do you add more ammonia. If ammonia is zero but nitrite is over 1 ppm, don't add any more ammonia till nitrite has fallen.

The best thing you can do is empty the tank, refill and add a 3 ppm dose of ammonia - and then follow the instructions about when to add more ammonia.

 

[wingfeet]

Thanks for the reply.

So if tomorrow I read that my Ammonia is 0.25 and nitrite is over 2.0 I wait a couple of days to see if Ammonia drops to 0ppm and hopefully nitrite drops too.

Basically we are looking for nitrites to drop now.

 

[wingfeet]

My ammonia drops to 0.25 within 12 hours if it helps

 

[Essjay]

You have grown just about enough of the ammonia-eating bacteria, but you haven't enough of the nitrite-eating ones. Because you've added more ammonia than you should have, the level of nitrite will now be sky high. I expect it is showing the highest colour on your tester chart - this means it is some value above that highest colour and depending on just how much ammonia you've added, it could well be above 15 to 16 ppm, the level which stalls the cycle. This is why I suggest a big water change to remove all the nitrite then adding 3 ppm ammonia and following the instructions in order to keep your nitrite level ever getting to that stall point.

If you don't want to do a water change, keep testing for nitrite and don't add any more ammonia until the nitrite level drops below 1.0. This could take some time if you have already added a lot of ammonia.

 

[wingfeet]

Hi
How long roughly would it take for nitrite level to drop from tonight if I don't add any more ammonia.

Thanks for the information

 

[Essjay]

That is impossible to say. There are just so many variables involved.

 

[Gruntle]

Ammonia bacteria multiply roughly every 8 hours (doubling the size of your colony, so in 24 hours it grows to 8 times the size of the original).
Nitrite bacteria multiply roughly every 24 hours.

Adding more ammonia means there's an increasingly higher and higher level of nitrite which, as essjay stated, will cause your cycle to stall once it gets over about 16ppm. Roughly speaking, 1ppm ammonia converts to roughly 2.5ppm nitrite. So adding more than 7ppm ammonia (in total) before the nitrite bacteria catch up MAY cause your cycle to crash. Which is why you shouldn't be adding more ammonia.

The quickest thing to do is reboot your cycle by performing a water change (as much as possible, turn your filter off and siphon the water right down to the substrate). Replace with conditioned water, leave it for an hour, check your ammonia level and boost it back to 3ppm, then wait. Doing so will not affect the bacteria you have at the moment, and your cycle should continue.

 

[wingfeet]

Alright guys

I have done a big water change (90-95%)

I took readings after an hour and read as follows

Ammonia-0.25
Nitrite-2.0
Nitrate-between 20-40

Added Ammonia to bring it to 3.00ppm.

Now do I do as you said and wait three days and check again for Ammonia to drop and nitrite to drop too.

Can I keep you updated on what I'm doing so I get the cycle 100%

Thanks

 

[Gruntle]

What you're now waiting for is this:

If at any time after the first ammonia addition (Dose #1) you test and ammonia is under .75 ppm and nitrite is clearly over 2 ppm, it is time to add more ammonia (Dose #2). Add the same full amount as you did the first time. Now, begin to test the ammonia and nitrite levels every other day.

So keep testing every three days until your ammonia is under 0.75ppm and your nitrite is over 2ppm.

 

[wingfeet]

Okay guys I've done a test this morning and results are as follow

Ammonia-0.25

Nitrite - 0

Nitrate - 80

Do I give it a maintenance feed of 1/3ppm or 3.00ppm or do you wait until Ammonia is under 0ppm ?

 

[wingfeet]

Looks like Nitrate is between 40-80ppm as I let it settle.

 

[Gruntle]

Add a full dose of 3ppm and test in 24 hours. If both readings are zero, then I'd suggest another dose of 3ppm and testing in 24 hours, and if that is also double zeros, you're complete.

If you are still getting readings above zero for both tests, then it's dose, test 24 hours later and then dose the next day (provided your readings are 0.25ppm or less for ammonia and less than 1ppm for nitrite). So you'd be dosing every second day, but testing every day.

You're nearly done! The key now is not to rush straight to the fish store and stock your tank as soon as you get double zeros, another day won't hurt (and will be better for your fish). And make sure to do a huge water change before adding fish, which will bring your nitrate reading back down as close to zero as possible without affecting your beneficial bacteria.