I keep losing vision in one eye. Between 5 and 30 min. I don't get a migraine after. Opthamologist says my eyes are fine. Must I see a neurologist?

Be seen. You should be seen promptly. This could be a variety of things which need assessment. I would urge you to see a neurologist as soon as you can.
Yes. Migraine remains possible, transient vision loss should always be further investigated. Neurology is the next step if eye exam was normal.