My new pump and air separator came in and are installed. The new pump had switch that changes the speed but it was broken I was able to test it out at low speed. It was working well I was able to heat up the fish water to 71F. I do think I will run the pump on med speed that way I can run the water through the heater a full speed.
But even at low speed the heater was sending 45C, 113F water through the loop. This is with the natural gas setting on the lowest setting.
I will be setting up my controller this weekend.