downgrading help

[bigcucumber]

Im looking to set up my 20gal Nano again and take down my 75gal reef.

Going FOWLR.

anyhow.. can i just setup 20gal add new deep aragonite sand bed and add water rocks corals and fish from main tank?

and be okay? no cycle?

also thinking of drilling 20gal and making a 10gal sump to go along with it..

[ratherbediving]

Some more info on your 20 gallon might be useful... what kind of filter are you going to be running (protein skimmer?) and would that filter be running on the main tank until you did the switch? How many fish (and what size) would you put in the 20 gallon etc.

Since your live rock will be able to do a lot of the biological filtration, you might be fine; but if your bioload on the 20 is too high right off the bat, you might not be. If you could add the fish gradually, that would be better IMO; that would let the sand bed time to start to establish a biological filter as well...

I'd consider adding a small amount of sand from the established tank as well.