We just brewed an all grain pilsner with saflager 23 yeast on a Saturday afternoon. We pitched two packs in cooled down wort and placed in fridge. We didn't have a very good thermometer until Sunday. When temp. was checked the fridge was about 45 degrees which is too cool for yeast to start fermenting. We put the carboy down in our basement for now which registered 55 degrees. It is now Monday afternoon and no activity has started. Is this ok and does it take a long time for lagers to get started. This is our first try.