Wow, sorry raultsu another thread that slipped through the cracks. Hopefully you found a good height and intensity by now. Had I been able to respond promptly, I probably would have suggested 10-13" above the tank at 60%-70% intensity, but while utilizing the EcoSmart Live's acclimation modes.
Please share what you ended up going with and how your 40B is doing...possibly a pic?? [emoji4][emoji4]