I have been taking 2 mg of clonazepam at night for years, and i'm weaning down to 1.5 now. is it safe to introduce 1 mg melatonin at night with it?

Yes: Melatonin is a naturally occuring hormone produced by the pineal gland as it gets dark out, in order to prime us to sleep. Use of many medications, including benzodiazepines and alcohol, may impair our melatonin response. Doses from 1-3 mg are safe and effective, and actually may work better than higher doses (5-10 mg). I wean people by 0.25 decrements, rather than 0.5 though.

Yes.: Weaning clonazepam is a good idea. Melatonin is safe to take with it. Doses are unclear: anywhere from 1 mg to 6 mg are used. It is not a soporific: doesn't make you sleepy. It is a zeitgeiber: tells your brain that it is sleep time.