Hello all, I can not seem to find the answer anywhere. Is the GHL Profilux Doser 2. A stand alone unit? Or does it need the profilux controller? I am shopping for an Automatic Doser. But I need a reliable stand alone doser since I do not own an aquarium controller. (Also if you know of any other stand alone doser brands feel free to input your opinions. Id like to place the order today thanks for all the help.)