I purchased the one gallon product and added the separate activator to begin it's use. I shook the activator thoroughly before adding to the Cactus Juice and then shook the gallon to mix the two components. I found small chunks of the activator floating within the jug and repeatedly shook quite vigorously several time to mix the contents. Thus far, still have activator solids floating in the cactus Juice. Is this a problem, or am I now going to have to filter the Cactus Juice before vacuumin

This does happen from time to time and I believe it is related to the temperatures during shipping during the winter since it is seldom an issue in the summer.  If you are not in a hurry, allow your Juice and activator to sit overnight, then shake well the next day and it should dissolve.  If you are in a hurry, you can get a piece of window screen and pour the Juice through it which will trap the undissolved parts.  Then simply crush the particles through the screen and pour some Juice in the screen again to wash the particles through.  Another option is to place a smaller quantity of Juice in a container with the undissolved particles and place this in your vacuum chamber.  Pull a full vacuum on it for a few minutes, then pour it all back in the jug and shake well.  The vacuum will help wet out the undissolved particles and they will then mix properly.