if dairy is a problem another option is REAL sauerkraut. here is a link to the rejuvenative foods site that sells kraut and kim chee with active probiotic bacteria in it.
i don't believe you need to take probiotics everyday once a healthy colony has been established, but you may want to do it everyday at the beginning. as far as when to take them, thats a good question. i take them before a meal, but other say after is better, not really sure.
i think any product that causes multiple liquid bowel movements throughout the day depletes the healthy bacteria. however, if you took one or two oxypoder caps a day, that would not be the case.