I dose mine daily since the Bubble Magus has the pumps, but I dont think its necessary to do daily. Mag drops pretty slowly. I think most people dose it up around 50-100ppm once it drops that much. So see what your starting mag is, get it to an acceptable level that you want to run it at. Then test every week or so and see how fast it drops and then figure out how much you need to replace that. I dont think you need to dose mag daily though, you will be dosing pretty small amounts as it doesn't drop much. The thing with dosing by hand is that as your corals grow you will need to dose more and more. Right now im dosing 170ml of CA/ALK every day, and I dont even think I have that much coral. So you will need to spread out your doses or it will be too much all at once.