Gear picks

Dosing reagents

Dosing is where the math on this site pays for itself, because the right product is a direct function of how much alkalinity your tank consumes per day — and that number is small. Once you know it, the decision is mostly about labor and cost per gram. The budget reality is that two-part is just chemistry: sodium bicarbonate (or carbonate) for alkalinity, calcium chloride for calcium, magnesium salts for magnesium. Buying pharmaceutical-grade dry chemical in bulk and mixing your own is by far the cheapest way to dose a reef, which is why the BRS-style pharma reagents anchor the budget end — a tub lasts a heavily-stocked tank the better part of a year. The catch is that it's two or three separate additions to keep balanced, plus mixing. That's the gap an all-in-one like Tropic Marin All-For-Reef closes, and it's our value pick: one bottle that supplies alkalinity, calcium, magnesium, and trace elements in the ratio corals actually pull them out of the water, so you dose a single thing and stop chasing ions against each other. It costs more per unit of alkalinity than DIY two-part, but it removes the part of dosing people get wrong. The premium consideration isn't a different chemical so much as the precision of delivery — a controllable dosing pump turning your daily demand into a hands-off schedule. Whatever you pick, size the pack to demand, not to the tank's gallons: a lightly-stocked 120 can burn through less reagent than a packed 40-breeder. That's exactly what the precision sizing on our dosing calculators is for.

Budget pick

Arm & Hammer Baking Soda — 13.5 lb

~$10

Plain baking soda is the cheapest alkalinity source there is — bake it at 250 °F for an hour to convert to soda ash, or dose it raw.

  • · Pure sodium bicarbonate
  • · 13.5 lb bulk box
  • · Bake to convert NaHCO₃ → Na₂CO₃
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Value pick

BRS Pharma Calcium Chloride (Ca component)

~$25

The calcium half of BRS two-part — anhydrous CaCl₂ dosed against Randy's recipe to track alk consumption gram-for-gram.

  • · Anhydrous calcium chloride
  • · Matched to BRS recipe calculator
  • · Pairs with the bicarb component
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Value pick

BRS Pharma Magnesium Mix

~$25

The chloride+sulfate blend Randy Recipe 3 calls for — keeps Mg topped up so your Ca and alk dosing actually holds.

  • · MgCl₂ + MgSO₄ blend
  • · Matches Randy Recipe 3 ratio
  • · Dose only when Mg tests low
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Value pick

BRS Pharma Sodium Bicarbonate (alkalinity component)

~$25

Pharmaceutical-grade sodium bicarbonate matched to the BRS two-part recipe — the same chemistry as baking soda without the oven step.

  • · Pre-portioned to BRS recipe math
  • · Raises alk without pH spike
  • · No baking/conversion needed
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Premium pick

Tropic Marin All-For-Reef (liquid, 1 L)

~$35

One bottle covers calcium, alkalinity, and trace elements in balance — the simplest dosing system that still grows SPS.

  • · Single-part balanced supplement
  • · 1 mL / 25 L / 1 dKH consumed
  • · Includes trace elements
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Dosing reagents — reef gear picks — reefcalcs