I used Orca and Hydroguard my first grow and the stuff worked wonders. I personally feel you could ditch the H/G cause Orca has the same strain, plus more.
A mini fridge is going to piss you off so just step in with a chiller and do it right straight away. Honestly, I think if you ran sterile you could get away without a chiller, so long as your res isnt seeing 75+. Dunno about bennies but I ran without a chiller for awhile and was ok. I saw a huge growth spurt when I got one though.