ReefWise
For manual-testing reefers

Reef chemistry,
done right.

The only reef calculator that shows your correction dose and your daily maintenance dose on one screen. No spreadsheets, no guesswork — just the right amount, today and every day.

Free during early access. Sign up to use the calculator and parameter tracking.

Alkalinity
10.9g NaHCO₃
CalciumSplit 2 days
40.2g CaCl₂
Magnesium
151.8g MgCl₂·6H₂O
Daily maintenance1.9 g/day

Why this matters

Most calculators tell you one number.
That’s how corals die.

You have two dosing problems, not one. The correction dose brings your tank to target today. The maintenance dose replaces what your reef consumes every day. Mix them up and you either crash your chemistry or let it drift. ReefWise separates them — safely, clearly, in the units you actually measure.

How it works

Three inputs, two doses, zero guesswork.

Set up your tank

Volume, rock kg, sand depth — we subtract displacement so the math runs on the water that actually exists.

Enter your levels

Current and target ALK / Ca / Mg, plus the supplement you use. Brand-agnostic — BRS, ESV, Red Sea, Tropic Marin, raw chems, all in.

Dose with confidence

One-time correction in grams or mL. Daily maintenance based on your tank load. Exceeds the safe daily max? We split it across days automatically.

What you get

A real reef chemistry tool, not a spreadsheet.

Big-three coverage

Alkalinity, calcium, magnesium — supports NaHCO₃, Na₂CO₃, CaCl₂, MgCl₂, and brand-name two-parts from BRS, ESV, Red Sea, Seachem, Tropic Marin, Brightwell.

Safe-dose guardrails

Exceed the daily max on calcium? ReefWise splits the dose across days automatically. Never dump 50+ ppm of Ca in one hit again.

Net water volume

Subtracts rock and sand displacement from your gross tank volume so every calculation is based on what actually exists.

Parameter tracking

Pro: log readings over time, infer your tank's consumption rate, and get drift alerts before chemistry crashes.

Dosing schedule

Pro: from your readings, ReefWise generates a daily AM/PM split tuned to your tank's actual burn rate.

Shareable links

Save any calculation and share it with another reefer. They open the same calc — no account needed to view.

Pricing

Free during early access.

Every account gets full Pro access — calculator, parameter tracking, drift alerts, dosing schedules — at no cost while early access is open. No credit card required.

  • Correction + daily maintenance calculator
  • Multi-brand supplement support
  • Net water volume helper
  • Shareable result links
  • Parameter logging with trend charts
  • Drift alerts before chemistry crashes
  • Dosing schedules tuned to your tank
  • CSV export

When Pro becomes paid, every early-access account gets notice well in advance.