Rye's Fishless Cycle

[waterdrop]

Yes, the nitrate(NO3) related products of the cycling process include a small percentage of nitric acid, which drives the pH downward. Different people's source water can contain differing amounts of various dissolved minerals. Some of these minerals can serve as the negatively charged ions that neutralize the protons (H+ ions) present when we have acids. This is called buffering. People who don't have many of these minerals don't have much buffer. When the nitrogen cycle is running (it runs at a high pace in a fishless cycle) and the buffer runs out, the pH will drop (and drop rather quickly.) When the pH drops rather quickly, the bacteria won't like it and will stall out the nitrogen cycle and stop working. Bad stuff! A large (90% = down to the gravel) substrate-clean-water-change will get a lot of the nitrates and nitric acid out and will refresh the tank with new tap water that will contain fresh buffer. This is usually enough to get things nicely on track again but if its not and these events become a problem, there are other things we can turn to.

So do a large water change(90%) and use good conditioner (Prime, for example) and rough temperature matching (your hand is good enough) and don't forget to recharge your ammonia! Give it 20min and re-test and log your results.

~~waterdrop~~

 

[Ryefish]

i have a feeling this will be a every-other-day occurance lol. So, the change in PH is because of my Na's, and thats why they are dropping low at the same time as my PH? I had to read your post a few times before my brain could attempt to understand it (been writing assignments all night, i think my brain needs sleep). They seem to recover really well once ive done a water change, as you can tell from the readings.

Im hoping my tank will be ok to be left until tomorrow afternoon to do the water change. Ill post again tomorrow after 6oclock readings

 

[waterdrop]

Oh yeah, you're fine. When the pH drops down past 6 the bacteria just stop processing, they don't die. The nitrate(NO3) does not behave nicely like you are describing. We don't "set much stock" in NO3 readings during a fishless cycle. We do them sometimes, in the hope that they will make us feel better. But they are simply not very reliable. First, the tests themselves are notoriously flakey, the second reagent sometimes just doesn't work right.. the shaking times are minimal to get the job done.. all sorts of problems with the test itself. Secondly, the test gets even less reliable if there's nitrite(NO2) present and often we've got lots of that around! So you just have to take it with a grain of salt.. always.

The nitrate(NO3) test really comes into its own -after- cycling. Its a really good regular test to do to see if your maintenance routine is staying up to snuff. In the non-nitrite stable running tank, the test is more reliable and more meaningful. Don't get me wrong - it can be reassuring to see that the fishless or fish-in cycle is indeed producing some nitrate(NO3) but overall its a better test for later on.

~~waterdrop~~

 

[Ryefish]

Carried out a 90% water change, dosed ammonia and left the tank to run for half an hour and did the tests:

PH: 7.4, Ammonia: 5, Nitrites: 1, Nitrates: 5

The nitrites were behaving today and didnt turn purple at the bottom of the tube. Probably related to the water change... i think...

I can't do any tests until after 10pm tomorrow as im out from 5am (ARGH!! ) and probably wont post results until monday afternoon

 

[waterdrop]

Yes, the water change diluted the nitrites. WD

 

[OldMan47]

If you are having to change water every other day to hold your pH in line, it is time to consider using bicarbonate of soda instead. If you add a substantial dose, it will push your pH up to around 8.0 and keep it there. That should make it easy to get the cycle finished. After the cycle finishes, you will have choices about the desired pH for your fish and the method that you use to control it. A water change is always an option to control pH on an established tank because it will not be required nearly as often as on a fishless cycling tank. Other options, depending on the pH preferences of your fish, include using calcium carbonate in the filter in the form of crushed shell or crushed coral. Another simple and readily available form of calcium is a cuttle bone, like you might use for a pet bird. Snail people use them all the time to provide the calcium that their snails need for proper shell formation.

 

[Ryefish]

will bicarb make the water cloudy?

 

[OldMan47]

Bicarb should not make the water cloudy unless you fail to dissolve it properly. If I wanted to use a bit, I would dissolve it in a sample of my tank water then add the solution to the tank. That way the bicarb will be fully dissolved and cloudy water will be avoided.

 

[Ryefish]

ok. thank you. ill pick a tub of it up today.
I tested my tank as soon as i got in last night (around 11pm) and the PH was 6.8 Ill post the other stats later today when i do todays tests.

Its funny, because the cycle i started before i had to change the gravel had a PH between 7.8 and 8.

 

[Ryefish]

Day 11 (yesterday):
PH: 6.8, Amm: 0.5, Ni: off the chart, Na: 5

Day 12 (today):
PH: 6.6, Amm: 0, Ni: off the chart, Na: 5

Mum is on her way home with a tub of bicarb Topping the ammonia up too

 

[waterdrop]

Make sure its baking soda (bicarbonate of soda,) not baking powder. WD

 

[Ryefish]

It was definately bicarb of soda.

Day 13 -
PH: 8, Amm: 0.25, Ni: off the chart, Na: 5

 

[Ryefish]

Day 14 -
PH: 8.2, Amm: 0, Ni: off the chart, Na: 5

Topped ammonia up to 4
It would be nice if my ammonia was at 0 tomorrow.

If it does got to 0, any guesstimates of how long it will be before my Nitrite's will start going down?
About to hit easter hols, and its going to be a very boring two weeks as far as my tank is concerned i think.

 

[Ryefish]

Ooh la la!
Day 15 and my NitrItes are still sky high.... but so are my NitrAtes!! I finished shaking the bottle, put the drops in the tube, finished shaking it for exactly 1 minute and it was bright red - like around 160 red.
Im assuming this is good (please tell me if its not LOL), and means that the increase in Na's is because they are finally processing the Ni's?

So, Tests on Day 15
PH: 7.9 - slowly dropping
Ammonia: 1 - hmm.. i dont know if i over-dosed last night?
Ni's: crazy (5+)
Na's: just as crazy (around 160 or over)

I hope im excited for a reason lol

 

[waterdrop]

You are understanding the nitrogen cycle correctly ryefish - yes, its good news. This is the good sort of example when Nitrates(NO3) reinforce the other information and add a little to the story. Even though your nitrite(NO2) test is spiked and unable to show changes, the nitrates are telling you that the nitrite oxidizing bacteria (N-Bacs) have increased their numbers quite a bit!

The slightly difficult decision this brings up is whether or not to perform a large water change to get those NO2 and NO3 levels down. In your particular case, since the HCO3- is working well to keep the temporary hardness and pH up high, and the processing is obviously moving right along, I'd hold off at the moment and watch it carefully day by day. As soon as the pH takes a sharper turn downward, rather than just dumping in more bicarb I'd then do the large 90% water change and recharge with bicarb and ammonia after the water change. Be sure to gravel clean deeply (unless you have sand, can't remember) as part of the water change since the heavier N compounds may tend to hang with the gravel.

~~waterdrop~~