I've attempted our 2nd try at all grain brewing. I'm very concerned about the lack of bubbles in the fermenter airlock tube, after almost a week. We have a good 5+ gallons in the primary, and used (1) one Whie Labs WLP013 yeast as required. This 2nd one is an Irish Red recipe, and our 1st attempt at this did the same thing, with a different all grain recipe. I've agitated and shaken the primary daily. Am I being impatient? Should I add another yeast? Any thoughts or recommendations would be appreciated. Thank you in advance.