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How do I cycle a tank without fish?

Normally, I get the tank ready, wait a few days, put in some cheap starter fish and watch for the spike. This time I want to do it without fish.

I think I read somewhere I should act as if there were fish in the tank and put food in daily and all those things. Is this true?

I know it will take 6 weeks or longer, but what should I do during that period?

Hey indy, fishless cycling is usually quicker than with fish. It should only take about ten days


To do a fish less cycle, you need a source of ammonia. Pure ammonia not one with additives. It shoudl say on the product label if its pure or not.
To start you add enough ammonia so that it reads on your test scale (4 pmm). .Keep tract of the number of drops of ammonia you put in. So what you are doing, is adding a source of ammonia. This will then start the nitrifying bacteria by giveing them a food source. You have to monitor the amount of ammonia in the tank, keep it up around 4 ppm( and keep track of the number of drops to keep the ammonia level there too), then test for Nitrite, once you begin to read nitrite, you watch ithe nitrite level climb, as it climbs, you will only add the number of drops of ammonia to the tank each day, as you did to keep the tank at the 4 ppm level (Don't test for ammonia). At some point the Nitrite will peak, and begin to decrease. At this point you no longer need to add ammonia to the tank, test the ammonia level of the tank, if its zero, you can add fish immediatly, the tank is cycled, if the ammonia level is still high, wait a day or so, till the ammonia is at zero. You now have both colonies of nitrifying bacteria established, and are ready for fish.
I am a bit rushed here, so hopefully you understand the idea. If you have any questions, just askem...

Hi, Fuzzy. This would be a great addition to the FAQ's.