I use just a few things.
You only need a few.
These two add the NPK or those 3 numbers you see on various fertilizer babs at garden centers etc.
GH booster(maybe, will not hurt adding more certainly)
If the KH is higher, hard tap water etc, I will spike the CMS+B with some DTPA Fe(Sequestrene 330).
That's about it.
You might use some MgSO4(epsom salt) if the water is hard in GH, but it's mostly Ca and no or very little Mg.
Likewise, if the water is good for GH, you might add some K2SO4 instead of the GH booster(Gh booster is 50% K2SO4 anyways). Some folks might have very high NO3 in the tap, so they add K2SO4 in place of KNO3 etc.
But 3-4 things are about all you ever will dose.
Real easy once you do it just like any and every commercial brand you might try, which are mostly water.......with a tiny bit of fertilizer in it.
DIY ferts........1000X cheaper.
Do not be intimidated by the chem speak and jargon.
It's really easy.