Doing Fishless Cycle First Time...

[eaglesaquarium]

1ppm ammonia processes to 2.7 ppm nitrite and 3.6 ppm nitrate, approximately.

 

[BIGbadJOHN]

Test results for 8 am today were:

ammo: 0
nitrite: 2
nitrate 20-40

So the levels definitely are going down, just not fast enough yet. I don't know if I want to dose the ammonia back in just yet. I dosed it to 2 ppm at noon yesterday so it hasn't been quite 24 hours yet. Should I dose the ammonia back up now or around 7 this afternoon before I go to work? Will it hurt the bacteria if it goes that long without ammonia?

 

[eaglesaquarium]

The bacteria will be fine either way.


It comes down to your schedule. When do you feel more comfortable adding ammonia on a regular basis. If you would rather do it before work, do it later. If you prefer doing it in the morning add a little now. Things are going well. You are going to want to slowly increase the ammonia dose back up to 4-5ppm. I would wait another day before bumping it up because the nitrites haven't cleared in 24 hours yet, but tomorrow's dose should probably be a little higher than today's (~0.5ppm more or so).

 

[BIGbadJOHN]

Test results for 8 pm tonight were:

pH: 7.8
ammo: 0
nitrite: 0
nitrate: 20-40

Finally the nitrites have hit 0, but not in the amount of time needed. The bacteria are definitely developing now though so it shouldn't be much longer I would think before they'll convert 4 ppm of ammonia totally. I'm starting small though. I dosed the ammonia back to 2 ppm at 8pm tonight so I'll check again around 8am and hopefully ammo and nitrite are at 0 once again. If they are I'll go ahead and dose up to 4 ppm and see how it can handle it. So far I've only been cycling for around 7 days so I think it's moving along pretty well. A lot faster than the fish-in cycle!

 

[KittyKat]

For only 7 days in, those are unusually good results

 

[eaglesaquarium]

As stated above, things are going well for only 7 days in. This is one of the fastest fishless cycles I've seen. Was anything in your tank, or was your filter previously used before you started this cycle?


Keep it up!

 

[BIGbadJOHN]

For only 7 days in, those are unusually good results

Thank you ma'am! I can't take the credit though. It's the bacteria that's doing all the work.

 

[BIGbadJOHN]

As stated above, things are going well for only 7 days in. This is one of the fastest fishless cycles I've seen. Was anything in your tank, or was your filter previously used before you started this cycle?


Keep it up!

Not the filter, but I had used the tank to house my one betta for a short period of time to treat him. He's better and back in his small container for now though until I get his new tank properly set up. I just did another water test and the ammonia is completely gone, but the nitrites are over 5 ppm so the bacteria still aren't strong enough to handle turning it around in 12 hours. I know it says the nitrite to nitrate process takes a bit longer and the bacteria take a little longer to develop so I'm not worrying. Hopefully when I get up to head to work they'll be at 0 and I'll dose again. I guess maybe that filter from Petco just was saturated with bacteria. It's the only thing I can think of.

 

[BIGbadJOHN]

So I tested the water last night around 9 pm and it was showing just a hint of nitrite left. This was after I had dosed the tank to approx. 2 ppm ammonia at 8 pm the night before. So I guess I'm converting around 2 ppm ammonia completely to nitrates in about 25 hours or so. So last night around 9 pm I dosed it back up to 4ppm ammonia and and after testing the water a few minutes ago the nitrites are well over 5 ppm as expected. I'll probably dose more ammonia in when I get off work in the morning.

How long can I expect it to take at the point I'm at in the cycle for my tank to start converting 4ppm ammo to 0 nitrites in 12 hours? Like I said, I'm converting 2 ppm ammo to 0 nitrites in approx. 25 hours right now.

 

[eaglesaquarium]

Unfortunately, it is hard to predict. There are a lot of variables to consider, but the key to consider is how fast the bacteria can double in ideal conditions, which is close to a day. But, you are probably not dealing with ideal conditions, so that rate is probably significantly slower. That said, if you are cycling 2ppm in 24 hours, it shouldn't be too long before it can handle a larger dose in 24 hours - maybe a week. Then it might take another week or two before it actually drops to zero at 12 hours. 6 weeks is a reasonable average cycle period, so you are still WAY ahead of that right now. In general a decent rule of thumb for estimating is that each phase takes about 2 weeks. So, phase one, pre-nitrite spike should take 14 days. Then the amount of time for the nitrite to hit zero for the first time later is about another week. Finally the last phase getting to double zeros in 12 hours takes about another 14 days. Of course, all this is plus or minus one week for each phase. The cycle could happen in as little as 3 weeks (fairly rare, from what I understand), and up to 9-10 weeks (also fairly rare). I would think the more normal range is 5-8 weeks.

 

[KittyKat]

4-5 days? I assume it would take twice as many bacteria to do 4 ppm to 0 ppm in 24 hours, and double again from 4 ppm to 0 ppm in 12 hours (which isn't actually the case, but it may be a good enough estimate), so you need 4 * more bacteria than you have now. The bacteria should double in number in under 2 days, if the conditions are ideal..

 

[BIGbadJOHN]

4-5 days? I assume it would take twice as many bacteria to do 4 ppm to 0 ppm in 24 hours, and double again from 4 ppm to 0 ppm in 12 hours (which isn't actually the case, but it may be a good enough estimate), so you need 4 * more bacteria than you have now. The bacteria should double in number in under 2 days, if the conditions are ideal..

I think your and eagle's prediction are both close because, like I said, this last time I dosed the tank to 2ppm ammo it took it around 25 or so hours to convert it completely. That was around 2 days or so ago, or the time before last that I dosed the tank with ammo. Now that was 2ppm, but this last time I dosed the tank I dosed it with 4 ppm which was 36 hours ago now and I just did another water test and the nitrites are at 0. Now the nitrites could have hit 0 right at 36 hours or they may have hit it sometime between 24 and 36 because the last water test I did was at 22 hours after being dosed with 4ppm ammo. The reading at that time was off the charts at 5+ ppm. Anyways, the point is that even if it took the full 36 hours to convert 4ppm ammo to 0 nitrites that still seems to be around a 50% speed increase from the last dosing of ammo which was only a day before. So if everything stays on that path of 50% increases in bacteria I should be getting 4ppm to 0 in about 3 days total. That would be great! But maybe my math is off. Just thinking in layman's terms though. That would definitely be one fast cycle time though because that would put me right at 2 weeks time. I would be very pleased with that and will happily give it another week of ammo dosing to make sure everything is going well. Thanks for y'all's help. I hope y'all are getting some helpful info out of this experience along with all the great stuff I'm getting. I appreciate all the feedback!

 

[eaglesaquarium]

We have all been there before and "watching" other cycles is always quite interesting.

 

[BIGbadJOHN]

Well, I've been staying regular on water tests. I was expecting the numbers to drop a little faster. Like stated before, the last water test showed that the ammo had been converted to 0 nitrites in no more than 36 hours. Well, I did a test at 9 pm tonight. That's 36 hours after the last dose of 4 ppm ammo and it was still showing a good bit of nitrites. I'm not sure exactly how much. Is it just me or is it really hard to read the nitrite test? I would estimate it to be a little under 5 ppm. Why so much nitrite left after 36 hours? the last dose of 4ppm ammo got converted in no more than 36 hours. Maybe even less since I didn't test it but at 24 hours and then 36. Should I be worried about this latest reading? I haven't changed anything that I know of. One article I read on the cycle said that the nitrite bacteria need phosphates to thrive. I did add in some finely ground fish food at the beginning of the cycle and once again after I did the large water change, but do I need to add more? The article said to add in either a small amount of ground up fish food or a few drops of pH Down to supply the phosphates. What is causing my bacteria to head in the wrong direction here?

 

[eaglesaquarium]

You are staring at a Monet painting too close... all you can see is a series of dots! Back up a bit, no single dot in a fishless cycle is that important. You have to look at the overall trend. I warned you that you may not be as close as your current readings would have indicated. Most cycles take 5-8 weeks. You aren't really that close to that time frame yet. Relax. It isn't a big deal, really. Your cycle is coming along very nicely. Stay patient. It will come along, and you have gotten a lot more movement earlier than most other people. It will come along, just fine.


If it makes you feel a little better, add the tiniest pinch of fish food. DO NOT EVEN BUY PH DOWN. Adding chemicals like this to your fish tank are a BAD IDEA when you have fish. pH DOWN will NOT actually be effective at sustaining a proper stable pH. If you want to lower your pH (when fish are in the tank) use some bogwood, peat or other natural method - which will lower the pH gradually and be able to sustain that. This is all said, not even mentioning that lowering your pH is the LAST thing you would want to do during a fishless cycle. The bacteria grow best when the pH is above 8.0! Lowering the pH would be counter to that.


I am curious as to what has happened to your pH recently...