Free Reef Chemistry Calculators
Switch without
guessing.
Six tools, no account: convert dosing between brands, dose from your tank's measured demand, plan corrections day by day, calculate water changes, mix stock solutions, and get a free reading of ICP results from any lab. Every calculation is built on manufacturer-published data and shown in full.
FREE · FOREVER · WORKS FOR ANY REEF, ANY BRAND
DATA SOURCES
Built on what manufacturers actually publish.
Each conversion factor is derived from the manufacturer's official published documentation, product pages, official manuals, official calculators, or manufacturer-published dosing instructions. Source URLs and access dates are documented for each system.
Where a manufacturer does not publish enough data to calculate a defensible conversion. The brand is excluded rather than estimated. We list those exclusions openly:
- Red Sea Foundation ABC+. No published mL-to-dKH delivery factor for the target product
- Tropic Marin All-For-Reef. No published mL-to-dKH delivery factor
- ESV B-Ionic. No published mL-to-dKH delivery factor
- Triton Core7. No public static dosing factor; system uses personalized ICP-driven dosing
These may be excellent products. We simply could not build a defensible automatic comparison from the data their manufacturers publish publicly. If you currently use one of these systems. Use the "Calculate from tank consumption" mode below, enter your measured daily alkalinity demand instead.
Mix your stock.
Each packet becomes 1 L of dosing stock. Add salts to half the water first, swirl. Then top off, that's what keeps it from caking. Two minutes. Then you're ready to dose.
THE CALCULATOR
ALK conversion only. Cross-brand CAL and MAG comparison isn't possible, manufacturer formats vary too much. BioForge calculates CAL and MAG from your tank's measured demand in
Alkalinity only, competitor brands publish ALK dosing in standardized dKH units, making direct comparison possible. Calcium and magnesium dosing instructions vary by brand and unit system, so no reliable cross-brand conversion exists. Use mode 02 to calculate CAL and MAG from your tank's measured demand instead.
Raising alkalinity more than 1–1.5 dKH/day stresses corals. 0.5 dKH/day is the safe upper limit for most tanks. For calcium and magnesium, stay under 10–20 ppm/day.
FREE VERSION
This checker tells you which numbers sit outside range for your tank type, and orders them by a fixed priority list. That is where it stops. It reads each element on its own, so it cannot tell you which problem is causing the others, how much to dose for your volume, or whether a lone metal reading is real. For that, the full ICP Decode reads the panel as one system.
Import your sample results
Works with any ICP lab (Reef Labs, ATI, Triton, Fauna Marin, Oceamo, and others). Download the Excel file or PDF from your lab's results page, then choose it here. This reads the reported elements straight from the file, so nothing gets dropped.
From any ICP lab's results page or email, select all (Ctrl+A / ⌘A), copy, and paste below.
Or enter results manually. Leave any field blank if not tested.
THE BIG THREE
NUTRIENTS
ENVIRONMENT
HEAVY METALS from ICP-OES report · optional
Only used to size refill quantities to your actual correction. Leave blank and the cart defaults to one packet each.
Calculate how a planned water change will shift your parameters, and how many consecutive changes it would take to reach target values.
CURRENT PARAMETERS
NEW WATER PARAMETERS leave blank to use NSW reference values
Every unit a reef test result or a European lab report can arrive in. Type a number and every equivalent updates as you go — nothing to submit.
Two-part dosing leaves salt behind: the dKH precipitates as skeleton, the sodium and chloride stay, and top-off returns water but not salt, so salinity climbs. This works out how far, and how much tank water to withdraw to hold it flat.
YOUR DOSING
UNIT CONVERSION
8.3 dKH
Converting a number is not the same as knowing whether it is a problem. Mode 04 reads a full panel in context.
SALINITY CORRECTION
Withdraw and replace
Tank water to withdraw
—
US gal
Same volume in litres
—
litres
Share of tank volume
—
% of total water
Salinity drift is one symptom of dosing that has drifted out of balance. Mode 04 reads the whole panel that caused it.
YOUR BIOFORGE EQUIVALENT
Based on your tank
ALK, daily dose
—
mL/day of Core+ ALK stock
ALK, packets/month
—
Core+ ALK packets/month
ALK, monthly cost
—
Core+ ALK @ $5.50/packet
CAL, daily dose
—
mL/day of Core+ CAL stock
CAL, packets/month
—
Core+ CAL packets/month
CAL, monthly cost
—
Core+ CAL @ $8.50/packet
MAG, daily dose
—
mL/day of Core+ MAG stock
MAG, packets/month
—
Core+ MAG packets/month
MAG, monthly cost
—
Core+ MAG @ $9.00/packet
These are estimates based on your inputs. Verify your actual dose with an ICP test 3–4 weeks after starting. Your tank's real demand may differ. Run a Decode after your test →
Show the math
Batch 001 is mixed, ICP-tested and published; the chemistry these numbers assume is real and readable. The Starter Kit is live. Apply this dosing schedule to your first order today.
Buy the Starter Kit · $69CORRECTION PLAN
Safely restore your alkalinity
Daily correction dose
—
mL/day of Core+ ALK stock
Days to target
—
days at 0.5 dKH/day
Total stock needed
—
mL of stock for full correction
After your correction period ends. Run Tank Consumption mode to find your ongoing maintenance dose.
WATER CHEMISTRY REPORT
Your tank, analyzing
This is the free version
That plan uses a fixed priority list, the same order for every tank, and reads each element in isolation. It can flag low alkalinity and high phosphate without telling you one is driving the other.
The full ICP Decode reads the panel as one system: what is urgent versus what only looks alarming, which correction comes first and why, dosing math for your volume, a 7 and 30-day plan, and whether a lone trace metal is contamination or a lab artefact worth re-testing.
Free with any BioForge order · Basic report always free
Already know your plan?
These refills match the low readings above, nothing else added.
Buy what your tank needsTakes you straight to checkout with these items · New to BioForge? Start with the kit, $69
WATER CHANGE PROJECTION
After one 20% change
After your water change stabilizes. Use Tank Consumption mode to dial in your ongoing dose.
Buy the Starter Kit · $69METHODOLOGY
Every conversion factor, cited.
107.1 mL of soda ash solution restores 1.5 dKH in a 100-gallon tank.
Expand citation
Source: Bulk Reef Supply official Pharma Soda Ash instructions · accessed 2026-05-18
30 mL of Part B raises alkalinity by 2.2 dKH in 10 US gallons, direct manufacturer claim.
Expand citation
Source: Tropic Marin official Original Balling product page · accessed 2026-05-18
1 mL raises alkalinity by ~2.22 dKH in 1 US gallon, direct manufacturer claim.
Expand citation
Source: Brightwell Aquatics official Reef Code B product page · accessed 2026-05-18
1 mL raises alkalinity by ~3.1 dKH in 1 US gallon, direct manufacturer claim.
Expand citation
Source: Brightwell Aquatics official Alkalin8.3 product page · accessed 2026-05-18
0.1 dKH/day demand maps to 1 mL of #1 KH Complex per 100 L, derived from ATI official dosing chart.
Expand citation
Source: ATI Aquaristik official Essentials Mixed Reef product page · accessed 2026-05-18 · ATI's higher concentration claim (14,250 dKH/L) was set aside in favor of the conservative dosing-chart value.
V5.9 formulation · stock concentration 5,069 dKH per L · ICP-OES verified every batch.
View source logic
Sodium carbonate, sodium sulfate, potassium bicarbonate, and borax dissolved in 1 L RO/DI. Formulation published on /science · verified through Reef Labs ICP-OES on every production batch · archived at /archive
ALK is published in dKH, a standardized unit across brands. CAL and MAG are not: units, concentrations, and reference volumes vary too much for a reliable automatic conversion.
Full explanation
Some brands express calcium delivery in ppm per mL per gallon, others per liter, others only as "raise X ppm with Y mL in Z gallons" with no per-volume rate. No single conversion factor applies across brands. BioForge CAL and MAG are calculated from your tank's measured daily demand in Mode 02 instead.
1 mL of Core+ CAL stock raises calcium by 1 ppm in 10 US gallons · ICP-OES verified every batch.
View source logic
BioForge internal formulation data · empirical verification through Reef Labs ICP-OES on every production batch · archived publicly at /archive
1 mL of Core+ MAG stock raises magnesium by 0.51 ppm in 10 US gallons · ICP-OES verified every batch.
View source logic
BioForge internal formulation data · empirical verification through Reef Labs ICP-OES on every production batch · archived publicly at /archive
COMMON QUESTIONS
Before you ask.
How do I convert two-part dosing between reef brands?
Enter your current brand and daily dose in the conversion mode above. Alkalinity converts reliably because every brand publishes it in dKH, a standardized unit; the calculator uses each manufacturer's own published delivery factor and shows the derivation. Calcium and magnesium don't convert automatically — brands publish them in incompatible units — so those are calculated from your tank's measured demand instead.
Can I upload ICP results from any lab?
Yes. The free ICP interpreter on this page reads results from any lab — ATI, Triton, Fauna Marin, Oceamo, and others — as a spreadsheet, PDF, or pasted text. It is not tied to any lab's ecosystem or any brand's products.
Are these calculators free?
Yes — all six tools, no account, no email. The paid product is ICP Decode, a full written interpretation of your ICP results with a prioritized correction plan ($39, included free with the Starter Kit). The free tools stay free either way.
How much alkalinity does my reef tank consume daily?
Measure it: test alkalinity at the same time two days in a row with no dosing in between. The drop is your tank's daily demand. Enter it in the tank-consumption mode above and the calculator sizes your daily dose from your reef's actual biology instead of a chart average.
Do these tools require BioForge products?
No. The water change calculator, consumption math, correction planner, and ICP interpreter work with whatever you dose today. The conversion mode shows BioForge equivalents because that's what we make — but every input works with any brand, and every calculation is shown so you can check it.