Hi guspirinhes
CFL 150w
you should go between 8cm and 15cm from top seedlings.
And go as close as possible without burning the plants during the veg and flowering periods.
CFLs don't put out a lot off lux to far away so this causes people to have them very close to top off plants.
And if it's a rapid growing plant like most Autoflowering marijuana you need to monitor daily. Not to find burned you top buds.
( not a fan of CFLs )
Hope this helps and good luck with your grow.