Remote Dosing Pump

During Winter and summer months for maintenance technicians manually change the dosing level in watre supply. There are times in the year where the dosing limits could be altered sooner than the manual jobs that are being raised, potentially saving in a large chemical costs. Looking for a dosing pump to be remotely controlled from a Programmable Logic Controller (PLC) to dose at different set points depending on different circumstances. Ideally the pump would need to be controlled through a 4 – 20 mA control loop input or through pre defined digital inputs. If you know some pumps or systmes, please write with detailed specifications.