I have a 2 hp 27 gpm pump in the pond going to stations with 6 heads that total 18 gpm. This has been working great for 3 years. I recently took a second system off the city water supply and connected it to the pond supply. This system has lots of 1/2 and 1/4 round heads. The pressure is extreme on some of the stations. I thought about connecting 2 stations together in the controller, but read where this could damage the controller. My questions are.....will this overload my pump ? Is there a pressure relief valve that can be installed in the main line to manage the high pressure ? Thanks in advance for any help.