converting sauna --8 bulb T5 HO --too much?

[dshallpost]

Planning to convert a sauna that we never use to a grow space. I am thinking I will have one T5HO fixture for the room. There are benches at two levels so I can have orchids at various heights/distances from the light. I would like to grow a high (catts, small vandacious hybrids) medium (oncidium) and low (paphs and phals) by placing them higher or lower under this fixture. The room will comfortably accommodate a 4 foot fixture. I am wondering whether to go with a 8 bulb T5HO fixture. This would be very bright but I would keep the plants at varying distances from the lights. Would appreciate any thoughts/guidance on whether 8 bulbs is just too much . . . .Also, would appreciate any recommendations on vendors.