Aquarium Care Calculators

How to use this collection

Start with actual water volume because substrate, decor, and waterline height affect nearly every aquarium estimate. Then use related tools for equipment, dosing, and maintenance.

Buying guidance

For aquarium products, compare the calculator result with product labels, livestock needs, and tank conditions. Dose conservatively when fish, shrimp, plants, or invertebrates may be sensitive.

What to check next

Use related aquarium calculators to cross-check actual water volume, livestock sensitivity, heater watts, filter flow, substrate depth, dosing labels, and water-test results.

Start here

Which calculator should I use?

Start with actual tank volume, then use that gallon estimate for heater, filter, water-change, dosing, substrate, and weight decisions.

Setting up a tank? Start with Aquarium Volume, then Heater Size, Filter Flow, Substrate, and Tank Weight.

Maintaining water? Use Water Change, Conditioner, Salt, Medication, CO2, or Cycle Ammonia calculators.

Choosing equipment? Use heater, lighting, canister filter, stocking, and stand weight calculators together.

Tools

Aquarium calculators

Tank care calculators for gallons, heaters, and water changes.

Guides

Aquarium supporting guides

Long-tail pages help explain calculator results and give visitors useful buying context.

Aquarium Aquarium Water Change Schedule Guide Plan aquarium water changes by tank size, stocking level, change percentage, replacement-water temperature, and dechlorinator needs. Aquarium How Many Gallons Is My Fish Tank? Calculate aquarium gallons from tank length, width, height, and displacement from substrate or decor. Aquarium What Size Heater Do I Need for My Aquarium? Choose aquarium heater wattage from tank gallons, room temperature, target water temperature, and safety margin. Aquarium How Much Gravel or Substrate Does an Aquarium Need? Estimate aquarium gravel, sand, or planted substrate depth and pounds from tank footprint. Aquarium Heater Size for 10 Gallon Aquarium Estimate heater wattage for a 10 gallon aquarium using room temperature, target water temperature, and livestock needs. Aquarium Heater Size for 20 Gallon Aquarium Estimate heater wattage for a 20 gallon aquarium and check when to choose 75, 100, or higher watts. Aquarium Best Aquarium Heaters by Tank Size Use tank gallons and temperature rise to understand aquarium heater wattage ranges before comparing heaters. Aquarium Best Aquarium Filters for 20, 40, and 75 Gallon Tanks Compare filter flow, media space, and turnover targets for common 20, 40, and 75 gallon aquariums. Aquarium Canister Filter vs. Hang-on-Back Filter Compare canister and hang-on-back aquarium filters by flow, media space, maintenance, and tank size. Aquarium Glass Aquarium vs. Acrylic Aquarium Compare glass and acrylic aquariums by weight, scratch resistance, clarity, cost, and support needs. Aquarium What Size Heater for a 20 Gallon Aquarium? Estimate aquarium heater wattage for a 20 gallon tank based on room temperature and target water temperature. Aquarium What Size Heater for a 75 Gallon Aquarium? Estimate heater wattage for a 75 gallon aquarium and understand when two heaters may be better than one.

Charts

Aquarium charts

Use these chart pages for quick references, printable visuals, and image-search-friendly planning aids.

Aquarium chart Aquarium Heater Wattage Chart by Tank Size Use this aquarium heater wattage chart to compare tank gallons, temperature rise, and suggested heater watts before opening the calculator. Aquarium chart Aquarium Tank Weight Chart Use this aquarium tank weight chart to estimate loaded weight for common tank sizes, then compare stand capacity and floor-planning calculators. Aquarium chart Aquarium Stocking Chart Use this aquarium stocking chart as a cautious starting point before checking species needs and filtration. Aquarium chart Aquarium Filter Flow Chart Use this aquarium filter flow chart to compare tank gallons, turnover targets, and filter GPH.