Quickest You Have Ever Cycled A Tank, And How?

[kelly528]

I cycle mine in a few days:

1) Introduce a few fish
2) Wait a few days until the water starts to cloud
3) Drop in some mature gravel, filter media, etc. This is essentially like dropping them into a tank full of food at this point, so the population skyrockets really fast.
4) Poof-- the tank is pretty much crystal in about half a day!

My secret is to wait until there is tons of ammonia for the bacteria to eat.


EDIT: On a second note, this does not make the tank 'mature', it simply establishes the nitrifying bacteria. Remember, a type of bacteria can only establish a population once there is food for them to eat.

This is a very poor method. Why make the fish suffer? Why not put the gravel in and then put the fish in? A few hours wait for the fish to produce the ammonia won't kill the bacteria. They can last over a day with out ammonia. Also, if you are certain that your idea is completely solid, why not just put food waste in the tank and not fish. The food will break down into ammonia. Also, there are two different types of bacteria needed for a cycled tank. The first would be the bacteria that convert ammonia to less harmful nitrIte ( which is still very deadly), and then another bacteria turns the nitrIte into NitrAte.

I did it with 3 zebra danios in a 20 gallon. I guess depending on your fish stocking you may be able to seed with filter media faster.

 

[bitteraspects]

so all you have established is that this process will only work if you are putting the media in a smaller tank with a smaller bio-load.

the bacteria, will not double in 24 hours, as it can only accommodate the amount of available food. if less food is available to the new filter, the bacteria is not thriving as it was in the old tank, if the amount of available ammonia is higher than the bacteria in the media can accommodate, the tank will go into a mini cycle where the bacteria will attempt to repopulate to accommodate the amount of food.

so yes. if you take half of the media from a filter on a properly stocked 100g tank, and put it into a filter on a properly stocked 50g tank, it will be an instant cycle. same if you ere to put it into the filter on a 100g tank with half the stock.
however. if you have 2 100g tanks with the same stock, remove half of the media (as you said, should not be done more than 1/3, but were still discussing imaginary tanks here) and put it into the other tank, it will not be an instant cycle, it will go through a mini cycle where the other half of the media (the new media) will need to be populated. and this process does not happen over night. it will likely take close to a week for everything to completely even out

 

[Assaye]

Current fishless cycle going pretty fast. After 48 hours I had 1ppm of nitrites showing up and 0 ammonia after dosing to 5 ppm of ammonia daily. Nitrites have taken a few days to start clearing, but yesterday (after a week) I have nitrates showing up. Hope it will finish soon =)

Insta-cycled my new Stingray filter with a small section of mature media. Had 5 neons and a fighter in there (silly sick fish) and not had any ammonia or nitrites, and my nitrates have been slowly climbing. Yay!

 

[Tolak]

Per this topic, post #4, and one of the peer reviewed research papers here; http/cobweb.ecn.purdue.edu/~alleman/w3-a...r-behavior.html Nitrifying bacteria are capable of doubling in 24 hours. There are also some additional very good papers linked to in that post.

In the world of bacteria doubling every 24 hours is quite slow. The nitrifying bacteria growing in the media correspond to a certain bio load, not gallons of water. So, with reduced feeding, which reduces the waste production, the filter with 1/3 of the media removed, and the tank itself will have no cycling problems.

The imaginary tank is just that, most fishkeepers don't have such an easily divisible tank running. In the real world, on Thursday I took all the media from one large box filter, about 1/4 of the total media in a 150 gallon tub, and set up a 29 gallon with 17 small clown loachs I just got in. I added the same percentage of media from another 150, added it to a 55 that had 3 angels, and added 30 yoyo loachs. The first 150 is full of adult angels, a few corys, and a good size bristlenose. The second has about 25 bumble bee cats, and a few smaller angels. Much of it is guesstimating, and erring on the side of caution.

 

[JustKia]

Instant cycle here.
I took media from my canister and wrapped it around sponge filters for my cory fry and male bettas - the media in the canister supports my community tank as a little for each male betta was plenty, same with the fry.
Did the same for my sorority, just took a bit of media and popped it into the new filter - instant cycle as there was more than enough bacs to support a few female bettas.