Sounds like he is glass surfing in either response to seeing his reflection, water movement or just the new environment....
Sometimes they will stop after some time to adjust...but they can get pretty stressed if it is due to reflection-I would cover 3 sides of the tank and see if this helps any and even keep the light off on the hood for a day or so and once he calms down and adjust to the tank-start removing the covers one at a time and monitor response-replace if needed...I would use dark colored paper if you have some-anything will work as long as its not reflective...
Sometimes it can be the water movement especially in smaller tanks and even with a baffle they just won't tolerate it and you may have to remove the filter all together for awhile until he adjust to the new environment...but I would try the covering 3 side first...