Skip the tap, go straight r/o, you'll appreciate the quality difference and the stable pH changes.
Unless your GO Biothrive is low in nitrogen or calcium... I'd skip the cal-mag. Magnesium sulfate is Mag and Sulfur and cheaper (Magnesium hexaheptate/hexahydrate is mag and chloride, skip that garbage for your plants) and is only what your plants need, no extra nitrogen or calcium. Never used that crud in 15 years, have always used R/O and a balanced nutrient mix with plenty of calcium and nitrogen.
Pro-tekt is AWESOME during veg and stretch, quit using it about the second week of flower or you'll need a grinder to break up your cannabis. It also acts as a pH up, so be aware and add it last.
Skip the bud candy, water the first 2 weeks with .25g/gal of epsom salts, shouldn't need any more for the rest of flower.
Yes, you can use all those together
