Do I really need to buy?

[gobytron]

Reefwars, unless you can show me some documentation where all of a sudden water changes have gone from being great for nutrient export to poor to somehow poor, I'll have to chalk it up to your opinion.

Maybe one that's based on lfs info more so than anything else?

Good theory to sell more equipment.

I have posted a couple that indicate they are excellent means for removing them....with the added benefit of replacing consumed elements and trace metals.

For goodness sakes, just google water change nutrient export and enjoy the wonders of the Internet..you don't have to take it from me. You can see the same said by multiple, respected reef enthusiasts.

Has there been some new research on this?

Please post the articles, as I hAve, that as you say, state your claim as scientific fact.

I'll also reiterate

Of course coralline will consume dkh (yes, obviously calcium too).

No one is refuting this well known fact.

It won't be an issue until you have lots of coralline with alk and calcium in perfect balance which promotes both their consumption.

If you're just starting a tank, as is the op, it is a non issue unless your rocks are extremely coralline covered.

Regular water changes would and are more than enough to subsist your coralline growth and then some in a newly established system.

Especially a smaller one.

Buying a doser on a new tank because you're worried about your corallines consumption is silly.

Sorry.