DR90 and HPS lights

I have a 150w HPS light but once I move in a month or so Im going to be upgrading to a Secret Jardin DR90 which is 3ftx3ftx6ft.
I am planning on also buying another light and Im not sure if I should buy a 250w MH + HPS light and use the MH for veg then both HPS for Flowering or just go ahead and buy a 400w HPS and keep using my T5s for vegging.
I plan on growing either 4 photos or somewhere between 6-8 autos in soil.
If I have both the 150w and 250w HPS next to each other in the tent would that be hotter than just one 400w HPS?
Any suggestions would be welcomed.
Any questions will be answered.

I would go for a 400w HPS in an aircooled reflector if heat is a concern

I have never had heat issues which is why im asking if it would become one? How big of a fan would i need for a 400w hps?

6" fan with around 250CFM or 500m3/h.

This would be to filter and exchange effectively.

You could speed control it for winter running.



I use a 400w with a fan and filter setup just like above.




J