Red Sea Complete Reef Care 4-Part, Part 1: Calcium & Magnesium+
multi-part
Manufacturer data
As an Amazon Associate we earn from qualifying purchases. Buying through these links costs you nothing extra and helps keep the app free.
What one dose does
PARAMETER
1 ml / 100 L
Calcium
+1.4 ppm
To raise calcium by 20 ppm in 100 L: 14.3 ml.
Maker’s daily maximum: 14 ml per 100 L (14 ml for 100 L).
How it’s used
Leading part. Start per table (e.g., mixed reef 3-5 ml/100 L/day); other parts follow a fixed ratio 1 : 2 : 0.5 : 0.5. Retest Ca after 3 days, then weekly, and change Part 1 (others scale with it).
Cautions
• Always dose in numerical order Part 1 -> 2 -> 3 -> 4, 10 minutes apart
• Max daily rise: Ca 20 ppm, Alk 1.4 dKH (0.5 meq/L)
• Intended for systems WITHOUT a refugium/algae scrubber; use the 7-part program if you have one
• Dose all parts by Ca uptake only; Red Sea warns that dosing by alkalinity overdoses Ca and traces
Part of Complete Reef Care 4-Part
Sources
Potency and dose table from the Red Sea instruction manual (copy on manuals.plus, published May 2024). maxDose derived from the 20 ppm/day Ca limit (20/1.4 = 14.3 ml). Initial daily dose per 100 L / 25 gal (Part1/Part2/Part3/Part4 ml): Mixed reef growth-exceptional 5/10/2.5/2.5, great/great 4/8/2/2, coloration-exceptional 3/6/1.5/1.5; SPS dominant 7/14/3.5/3.5, 6/12/3/3, 3/6/1.5/1.5; Frags 7/14/3.5/3.5; ULNS 3/6/1.5/1.5. Adjustment: run 3 days, retest Ca, (desired-current)/3 = daily change; <2 ppm/day keep dose; drop >2 ppm/day -> adjusting dose of all 4 parts and raise daily dose; rise >2 ppm/day -> pause all parts. Desired-levels table: mixed reef Ca 465/450/430 with Alk 12/11.5/8 dKH; SPS 465/430/410 with 12/8/7; ULNS 410/7. Sold only as a kit (Small/Medium/Large, ~3 months supply). Launched 2024; Red Sea calls it chemically identical to the 7-part.