Crosby & Bakers DADY activity qoestion?

[Prairiepiss]

Ok I'm not happy. I bought a pound of Crosby &Baker DADY the other day to use in my first AG ferment. The wort is 10 gallons. I rehydrated 15 g in 95 f RO water. Then pitched after about 20 min. 8 hours later I really don't have any activity that I can tell. The fermenter temp was 73 f. I put a coat on the fermenter and a heating pad. I got the temp up to 79 f. Still nothing.

This was the first time using this yeast. So I rehydrated 15 g more with 95 f RO water. Waited 10 min. Added a little of the wort from the fermenter. 20 minutes later and I barely have any action. A very thin layer of foam on the surface. Some visible movement in the liquid not very much.

I'm use to my starters foaming over within 10 minutes.

How active should this yeast be?

Could I have gotten a bad or old batch from the brew shop?
If so? How can I tell.