Upgrading Tank from 40g to 112g

[chokami]

I am upgrading from an existing 40g to a new 112g and am wondering if I need to have the 112g go through its own complete cycle or if transferring the existing liverock, sand and water, in addition to adding new sand and saltwater, will let me avoid cycling?

Current 40g has approximately 70 lbs of live rock and a pretty nicely established sandbed, all of which would be moving to the 112g Only inhabitants besides a CUC are a clown, pseudochromis and talbot damsel.

Should I add a bacteria booster to the new saltwater or just let the existing bacteria do their thing?

I plan to add additional live rock over the next few months as my budget allows, hopefully bringing the total to around 200lbs when done. Will add a few pieces at a time.

[mcgyvr]

Do not transfer the sand... Use new dry sand (well rinsed)..
In general if you can get the tank setup with new sand/saltwater and just pull the rocks right out of one into the next then there may be little to no die off and no cycle will happen.. BUT always plan for a cycle of some sort to happen.. It will probably be short/minor but it will happen..

Same for adding new life rock.. The die off from shipping may cause a slight cycle..
I think new live rock should be "cured/cycled" in its own small container to ensure its not going to cause problems..

[chokami]

Thanks, Mcgyver. For my own curiosity, why should the old/existing sand not be used?

[Ztous]

Thanks, Mcgyver. For my own curiosity, why should the old/existing sand not be used?

The idea is your sand is collecting debris and waster getting "dirtier" over time. It's a nice chance to clean it all out and start fresh. Your best best is to keep a couple of cup fulls of old sand to transfer over a starting population of micro fauna.