Dosing pump question

[phi delt reefer]

l3 just adds an sl1 which measures ph and orp. Useless in my opinion - almost no one runs ozone anymore (i dont know why - i hear good things about it though!)

get the basic one and pick up some extra pc4's (the power bars)

or get a neptune apex - way better controller. I have the RKL and have not set it up yet but the APEX has way more features that will probably take Digital Aquatics 5 years to catch up too. Profilux is too complicated from what i hear - the APEX is the happy middle