Fuge lights set up vertically In AIO's can be challenging because you are not hitting the broad side of the chamber with the light. With IM tanks you can cut the black film away and mount the light on the back for better coverage,. I'm not sure if that's an option for you.
Only time will tell. There are too many variables for anyone to do more than guess at this point.
If your chaeto is growing well and there is no algae in your display, then it's working. See how it goes and report back..
PS- You will need to stay on top of the chaeto very diligently. With that vertical orientation there will be die off as the upper layer blacks out what is below...