So the question is has anyone used these kinds of pumps for their tea set up? Is air or electric powered better (keep in mind it would be used off grid)? Which company makes quality ones(I've heard that at least the shruflows crap out after a year or so)? Finally I've heard various things from different folk whether they even make that much of a difference to the microbes. Some say impellers break up and destroy them making the tea less helpful and others say there is still the same count of them in the tea regardless of of the size of them. Any thoughts?