1. It depends on how many bacteria you think you have. I guess as long as you don't exceed 4 hours per pass during remote programs and can handle whatever effects from die-off, there isn't a problem. Be careful about sweeps, though that you don't run them too long and kill all of the bacteria in the gut.
2. I find that unless I know what I am dealing with, I try to narrow down my options as to what I guess is going on, I will plug in my guesses and then a few general ones to boot. But like Joe said, I keep the loop time to 4 hours or less. As an example, I actually had to take my 17 yo daughter to the emergency room yesterday. She was in extreme pain in her lower abdomen, and I could not figure out what was going on. I am usually fine with taking some educated guesses, but she was in extreme pain. Now that I know what we are dealing with, I was able to plug in frequencies for her issue.
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