5 min.
Ask your self this: how many litres of water will be in the tank, how many litres of (salt) water will be in the log and how fast will that salt come out of the wood...
If it will fit why not?
You could attach it, but it wont start to cycle unless you add some food for the bacteria, it could be just as easy to add 1/2 (or a proportion suitable for the amount of fish that will go into the new tank) of the old media from the old tank when you setup the new one - less faffing about.
I would think that the amount of salt would be fine in the filter [see above] would be fine