I removed the fittings on my spindle and used these from eBay.
Fitting Metric M8 M8X1 Male to Barb Hose ID 1/4†6mm Brass Fuel Air Gas -i6
My CRP4824 Pro is in my basement which has HVAC and remains a constant 70 to 72 degrees. I only run one fan, so I think a 120mm rad with 1 fan would be adequate for my system. I use a small submersible pond pump, about 10 gals per min. My fans are 120v and start with a relay in the control system.