Clear snot can just be allergies (remove hay, bedding, and any dust source for awhile) or a minor respiratory infection that will clear on it's own but due to the risk of severe infections like pastuerella any rabbit should be quarantined, not bred, and their future at all in your herd reconsidered. Some will cull for any respiratory symptoms because pasteurella can wipe out an entire rabbitry but there are many other causes in rabbits that they can overcome on their own. Everyone has their own level of response but overall agreement is to never medicate in order to save the rabbit, especially for future use. If you do you might create a carrier who will infect everyone else or if you breed afterward you will continue to create rabbits that have weak genetics toward illness and need medicated when they run into things as well.