My stonies are finally taking off, and they have started to consume more than my water changes can replace. So, I recently started some threads and doing heavy research on dosing.
As I have recently come to understand it, you have to take stock of where you are, where you want to get to, how to get there, and how to stay there. Where you are, means are you using quality reef salt, how often are you doing water changes, and what are your current parameters. Where you want to get to, usually means the ideal parameters listed by Randy-Holmes and in reef books. How to get there, as I understand it, is to dose close to the maximum dose of the element that you are low in until you get to the target parameter number. How to stay there, means once you hit all your target parameters, then you stop all dosing, and check your weekly numbers to get your consumption rate. Once you have your consumption rate, you now of course have your replacement or dosing rate.
So, in answer to your original question, when do you start increasing the dose, you actually have to give close to the recommended maximum doses first until you get to the correct parameter level, then start decreasing the dose to maintenance doses.
Sorry for the long answer, but this is what I gathered from research and from answers I got here in the forum. So, I am regurgitating it, hoping that if I said anything wrong, one of the true experts can chime in and both you and I can learn

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