I think you could be fairly certain your whole system would be darn near the setting your chiller is set for based on your pump size.

If you're pumping 360 gallons per hour (minus whatever distance it's going etc), the number of times per hour the whole system replaces should be plenty to have almost even temps in every container.

I'd also confirm it with a remote thermometer like xcrispi says, then you'll have a real good idea after half a day where your temps are at all the time.