Calculator

Label Dose Calculator

Scale a manufacturer’s own dose ratio to your real water volume, with the label wording beside the answer.

What you’ll need

Your tank’s real water volume
A treatment with a transcribed label rule

1 Which treatment

Only treatments whose label dose we have transcribed from the manufacturer appear here.

2 Your water volume

Use real water volume, not the size on the box. Work it out.

Enter your water volume to scale the label dose.

This scales the manufacturer’s own ratio to the volume you give it. It does not choose a treatment, adjust an amount, or recommend a course. Always dose from the label on the bottle in your hand — formulations and instructions change.

The label is right. The volume usually isn’t.

Dose instructions are given per unit of water, and almost nobody knows how much water their tank holds. A tank sold as 20 gallons holds around 15 once substrate, hardscape and the gap below the rim are accounted for — so dosing the number on the box adds roughly a third more product than the manufacturer intends.

This scales the manufacturer’s own ratio to the volume you give it, across 17 transcribed dose rules from 15 formulations. Every answer carries the label wording it came from, the source link, the date it was read, and the arithmetic — so you can check us against the bottle rather than trusting us.

What it will not do is choose a treatment, adjust an amount, or suggest a course. Those are decisions for the label and, where the animal matters, a vet. Work out your real volume first if you do not know it.

Common questions

Does this tell me which treatment to use?: No, and it never will. It scales a ratio the manufacturer published to the volume you give it. Choosing a treatment means diagnosing a problem, which is a decision for you, your label and — where the animal matters — a vet. There is deliberately no function in this tool that picks a product or adjusts an amount.
Why do so few treatments appear in the list?: Only treatments whose label dose we have transcribed from the manufacturer are offered. A dose rule may not be published here from a retailer listing or a forum post, because those routinely paraphrase labels incorrectly, and a wrong dose is an overdose. That rule is enforced in the build rather than by editorial care.
Why does it keep telling me to check my real water volume?: Because the gap is larger than people expect and it lands directly on the dose. A tank sold as 20 gallons holds around 15 gallons of water once substrate and the gap below the rim are counted — so dosing the number on the box adds about a third more product than the label intends.
It shows a warning about my shrimp above the dose. Why?: Because a correctly calculated dose of something the manufacturer tells you to remove invertebrates for is still the wrong thing to add. If you have saved a tank profile, anything you keep that the manufacturer has not cleared appears above the number rather than below it.

Related tools

Aquarium Calculator

Work out true water volume, water-change amounts, and unit conversions — with every step shown.

Tank Profile

Save what lives in your tank once, then check any treatment against all of it at once.

Treatment Comparison

Put two or more treatments side by side: documented verdicts, ingredients, evidence quality and gaps.

The label is right. The volume usually isn’t.

Common questions

Does this tell me which treatment to use?

No, and it never will. It scales a ratio the manufacturer published to the volume you give it. Choosing a treatment means diagnosing a problem, which is a decision for you, your label and — where the animal matters — a vet. There is deliberately no function in this tool that picks a product or adjusts an amount.

Why do so few treatments appear in the list?

Only treatments whose label dose we have transcribed from the manufacturer are offered. A dose rule may not be published here from a retailer listing or a forum post, because those routinely paraphrase labels incorrectly, and a wrong dose is an overdose. That rule is enforced in the build rather than by editorial care.

Why does it keep telling me to check my real water volume?

Because the gap is larger than people expect and it lands directly on the dose. A tank sold as 20 gallons holds around 15 gallons of water once substrate and the gap below the rim are counted — so dosing the number on the box adds about a third more product than the label intends.

It shows a warning about my shrimp above the dose. Why?

Because a correctly calculated dose of something the manufacturer tells you to remove invertebrates for is still the wrong thing to add. If you have saved a tank profile, anything you keep that the manufacturer has not cleared appears above the number rather than below it.