More Info on Fishless Cycling

[Cooter]

I have read numerous articles on the internet about fishless cycling and have noticed a slight discrepency regarding the time frame for the cycling. I was wondering about a few points that are made during the cycling that have me slightly confused.

1. Adding ammonia, how long do you add? The articles that I have read either add ammonia for a specified time or until Nitrates reach a measurable amount with zero ammonia and 0 Nitrite. The question is, how long to keep adding ammonia before the cycling is complete?

2. Can one add fish, 3 or 4, after the nitrites have spiked, but not yet reached the level of 0? After the nitrites have spiked, would not the bacteria be increasing expotentially, therefore adding additional fish and ammonia help to build the bacteria colonies to support additional fish at a faster rate?

My main question is that it appears that fishless cycling is a realatively new way of "setting up" an aquarium and therefore is up to certain amount of interpretation of scientific knowledge. Has there been a thread, that I have missed, dealing with fishless cycling and the "rules" of it? If not, would it be beneficial to have such a thread begin or an article explaining what happens if one adds fish just after nitrites spike verses letting the nitrites get to 0 before adding fish.

Now, if I am all wet, being a little guppy, please set me straight and point me in the right direction, as more information is better than not enough.

 

[OCCFan023]

1) You add ammonia until your tank can get ride of the 5ppm (which is the amount you add) in one days time. So you keep the amount of ammonia in your tank at 5ppm, and if it goes down to 3ppm in one day, get it back up to 5ppm, and do this until the tank can get ride of the 5ppm of ammonia in one days time.

2) Dont add fish after the nitrites spike. after the nitrites spike the nitrates will build up, and then you do a large water change, then add fish.

3) there has been a bunch of fishless cycling threads, and articles linked on threads.

 

[JWright]

While the process of adding an artificial source of ammonia to a tank to get the biological filter rolling is fairly new, the steps of the nitrogen cycle in the tank are well understood, and not really up for much debate.

Nitrite is just as toxic as ammonia, and it would be a very bad idea to add fish while there are still detectable amounts of either compound in the tank.

~JW

 

[Iggy]

Hi Cooter and welcome to the tank!

The big guns already mostly answered your questions, so I will just fill in a little.

a) A fishless cycles is basically building up an tank resistance to 5ppm of ammonia PER DAY. At first, when you startup, you only add enough ammonia to get your test readings to about 5ppm. Over the next few days, your ammonia processing bacteria will only process a small portion of the ammonia in the tank so it will slowly go down, so just top-up the ammonia levels to keep it at 5ppm. After a few weeks (or less), your ammonia will reach 0ppm by the end of the day, which means your ammonia colony is large enough to handle that much waste. Now the 2nd cycle is still in process, which is the Nitrite cycle, just as deadly (suffocates the fish), and is produced by the ammonia-eating bacteria. This takes a little longer to grow, so you need to keep feeding the ammonia-eating bacteria (5ppm) every day, so they produce nitrite, so a colony of nitrite-eating bacteria can grow large enough to process all the nitrite created by the ammonia-eating bacteria, at 5ppm per day.

b) You keep adding ammonia daily till your nitrite and ammonia both read 0ppm after one day of adding 5ppm. At that stage, your tank can fully process both types of toxic wastes, so you need to do a very large water change (without drying out the gravel or filter components) to remove the 3rd type of mild waste, called nitrAte. Nitrate is only mildly toxic and requires a lot higher numbers to hurt your fish. Only plants AND water changes reduce (dilute) nitrate as it builds up slowly.

c) After your water change, you can fully stock your tank with all the fish that will reasonable work in your tank. 5ppm ammonia processing is a little overkill, so as long as your within normal stocking parameters, you can add them all at once.

So, to summarize:

i) Add ammonia daily, keep it at 5ppm till BOTH ammonia and nitrite levels hit 0pmm after 24hrs.
ii) Do a full water change, keeping the bio-media (filter and gravel) wet with dechlorinated water.
iii) Add all the fish your tank can stock at the same time.
iv) Do regular 25% weekly water changes to keep the nitrAte levels down and water clean.

Note: Fishless cycling has been around for about 20 years, but is not common practise because fish-stores make more money selling and reselling fish and chemicals than $1.50 bottles of ammonia!

 

[FroggyFox]

And just in case ya didn't find it, here's a link to Iggy's cycling thread: http://www.myfishtank.net/forum/showthread.php?s=&threadid=13406

Sorry, I wont kick the horse and answer the questions again...just wanted to point out that yes you are correct in saying that fishless cycling is somewhat new to the aquarium community. I think many professionals (like people who work for fish stores) dont know about it and dont trust it because they dont fully understand the nitrogen cycle that all tanks go through and dont want to spend the time and research the idea, take the time to test it and make it work for them...and DEFINITELY not to try and explain it to a new person because it doesn't take much to mess it up and they'd have people trying to add all kinds of cleaners to the tank with live fish or something

Also on the actual timeline...many factors (as Iggy's thread points out) change the actual timing of a fishless cycle. The fastest I've ever fishless cycled without any seeding and only cranking the temperature up was about a month...and the fastest I've ever cycled with using all the tips and tricks was two weeks. (not including just moving a cycled filter to a new tank or using biospira that instantly cycles a tank)

I have had a couple of instances where my nitrite appears to be stuck peaked and wont come down because of the very very high nitrate level. I dont remember if Iggy's article covers this or not...but if this happens and your nitrite is stuck way up for longer than a week or so I'd do a big water change and then continue adding ammonia daily and see if the nitrites come down. Like they said...you add ammonia until after the big water change at the end...what really makes your tank "cycled" is the 0 ammonia, 0 nitrites and low nitrates.

 

[Iggy]

Ya... just to follow up... during a fishless cycle, some ammonia products break down chemically during the process and really mess with your pH levels, which can slow-down the nitrite-eating bacteria growth. Test pH every 3 or 4 days once your ammonia hits 0ppm just to make sure it does not happen to you. (pH above 6.8 and below 8.2)

If it does, a full water change and keep adding ammonia will solve it.