Moved a brown ale to secondary fermenter. It is an extract brew. Been in primary for a week. Gravity is 1018 and final gravity should be 1012-1013. Plan to keg in week. Will the gravity drop in the next 7 days in the secondary or not?
Hard to say for sure. Take another gravity reading in 3 days. If it's still at 1.018 it's done fermenting. If it's lower, wait another 3 days and take another reading. 2 of the same gravity readings a couple days apart is the best way to tell if fermentation is complete.
There is NO REASON to "secondary" an extract brew unless you need your fermenter to start another one. Better get another fermenting bucket they are cheap/
I agree, no reason really to use secondary unless you're doing a big beer that you want to bulk age or reuse your yeast cake. It won't hurt anything though as long as your sanitation is good.
And 68 is a good temperature. Shouldn't have caused a stalled fermentation so you're just gonna have to wait it out.