How big Chiller should I get?

[LAX Noob Reef]

Trying to prep for California summer, and it's about to get dry hot. Total water volume about 140 - 145G (120 top / 40B sump bot.) Would a 1/10 work? I see used 1/3 chiller for $600, but will I really need that much??

 

[bblumberg]

1/4 or 1/5 hp will be fine. 1/3 is overpowered and also larger format (at least JBJ are). Be careful with used chillers. I have had good luck with JBJ (2/2) but not so with Aqua Euro (1/1). There is a 1/4 hp on OC Craigslist that you might consider...