About DustyFish
What this is
DustyFish is a small, independent site about keeping a healthy home aquarium. It exists as a set of calculators for the arithmetic every fishkeeper runs into — tank volume, stocking, heater size, water changes, substrate, and salt dosing — plus the guides and a museum built around that same subject.
The tools
There are six of them, all free, all running in your browser:
- Aquarium Volume Calculator — how much water a tank holds from its dimensions, in US gallons, litres, and cubic units, with a net figure that allows for substrate, décor, and headspace.
- Fish Stocking Calculator — whether a tank is under, well, or overstocked, using the inch-per-gallon rule against each species and count you add.
- Aquarium Heater Calculator — a wattage estimate from tank volume, room temperature, and target temperature, rounded up to a heater size you can buy.
- Water Change Calculator — how much water to remove for a partial change and how much dechlorinator the replacement tap water needs.
- Aquarium Substrate Calculator — the pounds or kilograms of gravel or sand needed to cover a tank’s footprint to a given depth.
- Aquarium Salt Calculator — a freshwater aquarium salt dose in tablespoons and grams, at a general tonic, stress-relief, or ich-treatment strength.
How they work
Each tool takes a small set of numbers you already have — tank dimensions, a target temperature, a fish list — and runs them through a fixed formula or conversion. Nothing is looked up from a database and nothing is personalized; the same inputs always produce the same result.
Where the numbers come from
The volume, substrate, and water-change figures are geometry and unit conversion — length, width, height, and standard litre-to-gallon factors. The heater wattage bands follow the sizing manufacturers commonly publish for a given tank size and temperature difference. The salt doses follow the tablespoon-per-gallon ratios widely used in freshwater fishkeeping for tonic, stress-relief, and ich-treatment strength.
About the inch-per-gallon rule
The stocking calculator uses the inch-per-gallon rule because it’s the shorthand most fishkeepers already know, not because it’s precise. It ignores adult fish size, swimming behavior, bioload, and filtration, so treat its result as a rough starting point — not a stocking limit to build a tank around.
The museum
The Aquarium & Tropical Fish Museum is a separate, browsable set of galleries on freshwater fish, aquarium plants, equipment, and the marine reef. Its entries, images, and facts are drawn from Wikipedia and Wikimedia Commons, not written by us.
Guides & blog
Longer explainers — on cycling a tank, reading water parameters, or choosing equipment — live in Learn and the blog, alongside the calculators.
Straight talk about ads & advice
DustyFish is supported by advertising, not by any aquarium equipment or fish food brand, and isn’t affiliated with any manufacturer or fishkeeping organization it happens to mention. Every calculator gives an estimate based on the numbers you enter — it’s general information, not veterinary advice. If a fish is sick or your water tests look wrong, that’s a question for an aquatic vet or a water test kit, not a calculator.
Questions?
If something’s unclear or a tool gives you a strange result, get in touch.