So I've been researching a lot and have seen many different opinions on what lights to use for autos. I will be growing two royal dwarf autos to start out. Originally I was going to use two 42 watt CFLs 6500k lights to start, but then I read that hps lights were the way to go for autos and can yield more buds.. so I considered using A 75watt hps bulb. Not sure what HPS means either... Also can I use that same light for the whole grow or should I switch to 2700k when it starts to flower? Any input would be apreciated. Thanks!