Not as much slobber as expected

Hey,

This was my first time making Caribou Slobber(or any 1 gallon kit from NB, I’ve done 5 gallon kits before). It seems pretty short of a gallon(see attachment). Should I be covering the boil for some of the time to conserve water? I started with the 1.25 gallons like it said, so I assumed the extra was for the boil off. Directions never say if you should cover it or not.
Obviously just starting out here, so any tips will help.
Thanks!

Do not boil with the lid on. Either start with more water or top up to the correct level after you transfer to the fermentor. Either will work without changing the gravity because you only boil off the water not the sugar.

Thanks! I was definitely concerned about adding more water at the end. I’ll definitely do that next time.

And with the Slobber you might be better off not hitting the full gallon mark. It’s a very vigorous sucker and tends to ferment out of airlock.