There are many ways people cycle a new tank. This is how I cycle a new tank.

With my 55 gallon I arranged it the way I wanted and put water in it. I left it over night to make sure the temp. had stabilized. I then added 12 hardy fish (danios, swordtails, platys, mollies). I tested the water 2 to 3 times a week. The tests were ammonia, nitrite, nitrate and ph (you can test for water hardness to make sure your fish will be happy).

The first week the ammonia will rise, spike and then come down. When the ammonia starts to come down the nitrites will start to rise. This is because the by-product of ammonia is nitrite. The nitrite will spike and come down. When the nitrites are on the way down the nitrates will start to rise. This is because the by-product of nitrites is nitrates. The nitrates will spike and come down, but may not go completely away. You can add more/new fish when the ammonia is 0, the nitrite is 0, the nitrate is no higher than 20. This process can take from 4 - 8 weeks to complete. Some people do small water changes during the cycle, but I say it sets you back by not letting the bacteria fully establish. You can purchase live bacteria at the lfs/lps to aid in cycling. Ph should be where your fish like it as should the temperature. I added Novaqua to condition the water and Amquel to aid in ammonia removal (Amquel will not get rid of the ammonia completely, it will only help your fish by making it less toxic to them).

The other way I have cycled a tank (my 29 gallon) is to put about 1/3 of already cycled aquarium water in the new aquarium. I also grabbed a handful of gravel out of the cycled 55 and put it in the 29. I added 6 of the previously mentioned hardy fish and tested the water once a week. It took 2 weeks to fully cycle versus the 8 weeks with the 55. You can ask your lps/lfs for some gravel and water to jump start your bacteria colony.
This is not how everybody cycles a new tank. This is how I cycle my tanks.

After the cycling period, you should test the water once a week. The ammonia should stay at 0, the nitrites should stay at 0, the nitrates will be between 0 and 20 (20 is a little high). If the nitrates are high you may be overfeeding or have too many fish. Do a 30%-40% water change every 2 weeks, if you have an overstocked tank, then weekly or if the nitrites start to rise or if the ammonia starts to rise.

Good luck!

i agree with all that u said funky.

to add a little bit. instead of buying 'bacteria kits', u can also just buy some water off the LFS, many will do this and it is probably cheeper and more natural than using a 'bacteria kit' (the LFS may even give u the water for free). or if u have a friend with an established tank, get them to give u water from when they do a water change.

when i cycle a new tank, i use old water, some gravel from an established tank and also either use old established filters or if i am using new filters i fill them with old filter material from one of my established filters.

u did mention using tap water conditioner, but i would like to point out the importance of this, if one doesnt use tap water conditioner there is a danger that chlorine that is in most untreated water can kill the good bacteria and either slow down or kill the cycling process. this can even happen in an established tank, so always use a good tap water conditioner when doing water changes.

oops, oh well, some things are worth sayin twice

No problem. Can't be too cautious when lives depend on ya.

When I'm setting up a new aquarium I do almost the same as you guys but instead of adding a few fish I use a maturing agent called Biomature from Waterlife, which is basically a bottle of ammonia to add to the water like fish would and the cycle follows pretty much the same pattern, except you have to test daily to alter the dose as when the nitrite converting bacteria start showing up you normally halve the dose you add.

I got into the habit of doing this after setting a couple of marine tanks up a few years back and makes life easier, and can even be used to to fully mature a tank to full density for fish that need crowding in from the start like mbuna. Its also pretty useful stuff if you want to keep breeding or hospital tanks running but don't have or want any fish in them all the time.

ROFL, even more so because in this really old marine aqaurium book I had it actually recomended doing that as good way to start your tank off .

too funny. lol, i ment it as joke, but hey if it works it works

I'll have to dig out my notes from when I crash cycled my 250 litre. I think day one was fill up from the tap, and add water conditioner, turn on heater & pump/filter. Day two was add in the bacteria. Day three begin dropping in the 'test' fish. I think I was fully populated within 5 days. Test's were ok.

Seems a bit of a rush, but my other tank was so over populated, they were getting ill. I had to get them out of there.

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If the nitrates are high you may be overfeeding

Now, this has always interested me. Is this based on continual overfeeding? Because I've wondered if Nitrates can be generated direct from the food, as a source. Or is it absolute, that Nitrates in your water, must have been generated from the Nitites, which in turn from the Ammonia, in turn from the Fish. And while I'm on the subject, Ammonia, can it be generated direct from the food, or must it be processed by the Fish.

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as good way to start your tank off

Makes sense, that's what the fish do in there!

Does anyone have any timespan figures for the Nitrogen process? eg, if you had so much mg of Ammonia, how long does it take to become so much mg of Nitrate? I realise there's probably many subjective parameters to the process. But it's a damn good question!

Yes. Its along the lines of decay. Uneaten food can overload your bacteria colony in a matter of a couple of days if overfeeding is constant.

So my practice of not feeding on Sundays, 'to allow the tank to catch up', may be a good one, in that regard?