chiller setup to tee or straight thru

Im trying decide on how to run the chiller on my seahorse tank. Its 57 rimless with a 29g sump. I was wondering if I should tee off the return and return it back to the other side of the sump. I was seeing how well and accurate that would work.

Option 2 is to run the chiller directly inline on the return pump from the sump. This way all the water is chilled and think that the accuracy would be better. The only with this way is the flow might be to much for the chiller.

The return pump is a mag9.5 that is controlled with a valve for flow.

Also the heater....does it plug into the back of the chiller? My heater is a Catalina Aquarium that has its own control. The heater is in the sump and the sensor is in the DT. The heater has a ground so it will not work.

So how would I set the heater up?

Thanks