Cycling A New Tank From An Old One

[Tiger Tiger]

I decided to shut down a smaller tank whilst starting a new one so i swopped water, sand and filters into it.It's 50 litres more so i have added a new filter and some fresh sand.
Well, 72 hours later i have great readings with ammonia only very minimal and Nitrite OK.

I had done this once before a few years ago and expected a explosion of Ammonia and Nitrite but it never came and within 5 days i had fish doing well.

So why is this not done more often or perhaps members have. There was no infections from the old tank and after 1 weel i pulled the internal filter which had the original established media in it and the new ones worked just fine.

I guess if you only have one tank this can't be done but with multiples what's the problem

 

[Schmill]

My only warning here would be that 1 week was probably too soon to pull the old filter out. Chances are it was that that was keeping all your water test levels good whilst the other filter cycled. It will be quicker, but the figures I've seen mentioned on here still recommend running BOTH filters in the tank for at least a month...

 

[drobbyb]

My only warning here would be that 1 week was probably too soon to pull the old filter out. Chances are it was that that was keeping all your water test levels good whilst the other filter cycled. It will be quicker, but the figures I've seen mentioned on here still recommend running BOTH filters in the tank for at least a month...

It's called "cloning" a filter. 4 weeks is a good timeframe.