Flometer2

I was thinking of setting a doser to dose a set amount of ca/alk then test every week and adjust the dose. With automated testing devices that can control a dosing pump, this is done for you and I'm sure the dosing would not be constant like above. But how much better is this? Is Ca/Alk really bouncing around enough that this is better? Assume 1 yr old tank with medium coral load.

For my new ~ 1200L build I am planning 2 return lines and considered creating a manifold on 1 of them. Just to be clear, 1 pipe that sends water directly back to DT, and a 2nd pipe that flows back to DT but also has a manifold to feed media reactors and maybe a UV, this way I dont need individual pumps for each. But is this overly complicated? What are the finer pros and cons of having such a manifold? I have plenty of space in the sump, should I just place my reactors in the sump or externally but still feed by a pump from the sump. Once more question: Do all of you drain your effluent media tubing underwater in the sump? Is there any benefit to having the tubing en above the water and splashing down?