Which extractor fan for 600w HPS?

I am upgrading to a 600w HPS light kit and aint sure which extractor fan to get with it? I currently have a RVK100-A1, but would a RVK125 be good enough for the job? I am on a budget and need to get:

• A humidity/temp meter
• 600w HPS light
• More biobizz nutes
• An extraction kit (with carb filter)
• Delivery costs
• Possibly a light timer contractor

All for under £250!

So im hoping that i can get the RVK125 instead of a more powerful one!

BUMP... anyone?!

Is an RVK125-A1 suitable for a 600w hps in a 1 metre x 1 metre wide and 2 meter high tent?

you could go bigger but that should be fine. Are you going to air cool the 600 with the fan as well or just use for exhaust?

was just going to use the exhaust. in time im hoping to get a fan speed controller obviously. when i on wednesday i'll be getting a thermometer too so i have a rough idea of what the temps will be like.

Also, im 2 weeks into flowering with a 250w. if i switch to the 600w will my yield increase significantly?