Fishless Cycle

Wasn’t as low as I was hoping but believe it was just under 1.0 this morning so did dose #4.

one question...my tank has evaporated some along with taking water out for testing. Can I replenish the water so it’s not as noisy with the filter? If so do I dose conditioner for full tank or just what little I add back in? Thinking 2 gallons or so.
 
You can add the water back to the tank, dechlor it before it goes in. I do not remember which dechlor you are using. But those products which state that they detoxify ammonia do act to slow a cycle, but not to stop it. A small water addition to top up the tank with the normal dose of dechlor for that amount of water should not create any issues. Do not dose for the whole tank.

Basically, the bacteria want their ammonia in the for toxic NH3 form. Some can also use NH4, but they do so much less efficiently.

I am very curious to see how things test tomorrow morning. best result- 0/0. But I think it will be more like 0/some level of nitrite. It may even have a low reading for ammonia and some level of nitrite.

Assuming you do not get that 0/0, when you do get the .25 or below for ammonia and are clearly below 1 ppm for nitrite, dose it back to 3 ppm and wait 24. You should also be aware that it is not uncommon with hobby ammonia test kits to get a persistent low level reading for ammonia which is not really there.

We know it is a false reading because of the process. If there is more ammonia available than the bacteria need to thrive, the bacteria will reproduce. So if you add 3 ppm of ammonia and then you keep getting a .25 ppm ammonia reading day after day, it cannot be real. If the bacteria can handle 2.75 ppm of ammonia in 24 hours, they should reproduce to handle a real excess .25 ppm in a very short time. Maybe and hour or so. And if the bacteria are being killed off or stalled, then ammonia should build up much higher than .25 ppm.
 
I use API Tap Water Conditioner but I’ve heard a lot of people say one of the Seachem products is better so I may switch to that when this bottle is gone.
 
That is perfect for cycling. It does not detoxify ammonia. But, this also means if your water provider uses chloramine, water changes can result in a tiny ammonia spike. When chloramine is broken down it becomes chlorine and ammonia. In a cycled tank there should be so little ammonia that it is gone almost as soon as it is created.
 
I added dose number five today (2 days after #4). My ammonia was at zero and nitrate was clearly under one. Maybe I’ll be lucky and tomorrow morning will be zeroed out on both sides. Which would pose another question. I am leaving tomorrow mid morning and will be out of town until possibly Saturday evening. How do I handle that if it is cycled tomorrow morning? If it’s not quite cycled I figure I will be fine until I get back Saturday? Or do I need to add a little more ammonia to get it through until I get back?
 
Not to worry, the bacteria do not need to be "fed" every day. You can hold the cycle in a tank for sometime using ammonia. even if you are not quite a 0/0, add a full dose of ammonia before you lave. When you get back n a few days, do a water change and add ammonia again.

If you add ammonia every 2 or three days things work fine. In fact I have read papers dealing with waste water treatment where the flow of ammonia can get very high, drop very low and then up again and this seems to make the bacteria more hardy not less so.

The other thing to realize is that the bacteria have a strategy for surviving hard times. Because they do not form spores, they need another method. They can sense when ammonia and/or oxygen goes away. They respond by going dormant.When what they need returns, they revive. When talking a matter of days or months, the colony can become viable again pretty quickly. This depend on what condition they were in when they went dormant and then for how long they stay that way.

The upshot is, you do need to worry about being away a few days.
 
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If it isn’t cycled like I’m thinking/hoping it will be do you still think I should dose before I leave? Or only if both read 0?
 
I am thinking you have enough ammonia bacteria to handle 3 ppm in 24 hours now. So we are only talking about nitrite and nitrate. If the nitrite is not under 1, do a water change and then add the ammonia dose. That will reduce any nitrate as well.

You should be close to having the cycle complete. Bear in mind that when you do a full ammonia dose you are creating the potential for it to make a maximum of about 7.65 ppm of nitrite. Even under the assumption the conversion is not 100%, your tank processed a lot of nitrite in 24, just not all of it. So, the amount of bacteria that remain to be created from reproduction is not all that great.

It is somewhat important here that we top off your cycle. You really are close. So you definitely want to go away having added a full dose. Leave the bacteria happy and well fed and they will be fine. It should also bring you to 100% cycled. You will just miss being there to witness it.

It seems to me that it is about 25 days or so since you did the reset on your tank. I am pretty sure you will be cycled within a day or two if not already. So it was about 4 weeks. Not too bad, but you had made some progress before things got stuck. I tell people that a normal fishless cycle without any seeding and/or live plants should take 5-6 weeks.
 
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