While monitoring it is super important for long term success.
Popping in corals and doing your first test and dosing after 1 week isn't going to be a problem either. Nothing will happen overnight including complete depletion of the elements in your water (Maybe with a booming SPS reef sure but not for a few frags)
You'll get back from your coral and tank the time and detail you put into it.
@92Miata gave great info.
The main thing I'm trying to impart is to not worry TOO much about dosing until you feel like you have you head wrapped around it properly.
Overdosing, or incorrect dosing is just as harmful as not dosing at all.
If you keep your parameters stable and at a consistent level and good level for reef health including coralline from the second you start your tank, you'll ultimate have the best success. It's not to late to start now either, but his main point is stability is king, and there are many other things in your water that consume Alk besides SPS he is right.
You shouldn't see huge flucutations in any elements within 1-2 days though of just a few LPS and Softies frags. but they will consume it for sure.
since you have an existing tank, with coral (You have a biocube yeah?) I'd suggest if you want to not do WC's, start your plan with this tank and try to get more knowledgeable about dosing on it.
Start with daily testing now, no WC's. Over the next 2 weeks you'll see a difference in the Alk, Cal and Mag. I wouldn't dose for the first 2 weeks, this will give you some time to see how much the tank is consuming on a daily or every other day basis.
After 2 weeks start dosing every day or every other day along with testing, see if you can get the parameters stable after a couple months of toying around and learning about dosing.
You should be able to get it pretty easily.
More or less
ALK, CAL, MAG goes down dose to adjust, if it goes too high (higher than it was on original test) you've dosed too much. There's a lag on this as well after dosing, so just test once a day.
You will get all your answers just doing something like this rather than trying to read about it everywhere.
There's a lot of information about dosing and the best thing you can do for yourself is browse the sticky threads in reef chemistry forum if you want to read more.
however, It's all a gradient scale. Don't try to overwhelm yourself all at once.
Once you have dialed in dosing you can drop testing to once a week or once a month. Up to you. At that point its more of a monitor.
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also I'd use ATI instead of SeaChem to start btw. I don't like Seachem in general but just my own feelings. Both good beginner 2 part dosers.
There's no "perfect parameters" but rather ranges. (I only say this because the opinions differ so much on ideal numbers)
Do more study on Alk and the benefits of it in reefing etc, and decide for yourself what you want your alk, cal and mag to be at stably, get it to there and then work to keep it at that constantly, you'll be fine.