i was wondering how long it would take to cycle a 20g tank by adding gravel from my already cycled 10g tank. i am getting the tank tomorrow and how much gravel from my 10g should i put in the new tank.
how long
- Thread starter some_guy
- Start date
See the thread in this forum titled "how long did it take you to do a fishless cycle"... you'll find all the answers to your questions there. 
IME gravel isn't the best thing to use when you want to cycle a tank. You'd be much better off taking filter material from the 10g and putting that in your 20g filter.
The nitrifying bacteria prefer to colonize areas of the tank that have a high oxygen exchange. Typically the filter or biowheel would be the best spot because of the constant water flow. the exception would be in a tank with an undergravel filter. In that case, a couple of handfuls of gravel would help out. You would want to add a small bioload immediately though and closely monitor the levels being prepared to add either more bacteria from the established tank or Bio Spira.
I have set up three tanks off of an established tanks filter material. Each time the tank cycled immediately. The one time I tried using gravel it didn't work so well. It helped but it didn't cycle the tank.
Tom
The nitrifying bacteria prefer to colonize areas of the tank that have a high oxygen exchange. Typically the filter or biowheel would be the best spot because of the constant water flow. the exception would be in a tank with an undergravel filter. In that case, a couple of handfuls of gravel would help out. You would want to add a small bioload immediately though and closely monitor the levels being prepared to add either more bacteria from the established tank or Bio Spira.
I have set up three tanks off of an established tanks filter material. Each time the tank cycled immediately. The one time I tried using gravel it didn't work so well. It helped but it didn't cycle the tank.
Tom