View Shurflo Solar Pump Controllers here: https://www.altestore.com/store/Solar-Water-Pumps/Submersible-Solar-Pumps/Shurflo-Pumps-Accessories/c651/page/1/sort/3a/
John Wright from SHURflo/Pentair pumps discusses the advantages of using solar pump controllers, the 902100 and the 902200, with their 9325 solar submersible pump. With a pump controller, solar panel directPV Direct systems are able to pump up to 30% more water than without a controller. It will start the flow earlier in the day and continue pumping later in the afternoon, as well as improve performance on less than optimum solar days.