12V @ 5A max = 60W max (25W for fans, 25W for pump, 10W overhead safety for PSU)
5V @ 1.5A max = 7.5W max (5W for electronics and LEDs, 2.5W PSU overhead)
When you use a industrial psu (Meanwell, TDK,.. ) this is OK.
But when you use any of the chinese PSU models, plan 100% as headroom.