{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"aquarium-volume"},"result":{"entity_type":"calculator","id":"aquarium-volume","calculator_id":"aquarium-volume","canonical_url":"https://tttkmbb.com/everyday/aquarium-volume","name":"Aquarium Volume Calculator","title":"Aquarium Volume Calculator – Litres, Gallons, Water Weight, Glass Thickness and Stocking Estimate","category":"everyday","category_name":"Everyday Life","tool_name":"calculate_aquarium_volume","featured_mcp_tool":false,"description":"Computes the water volume of a rectangular fish tank from its internal length, width and height (cm or inches), the weight of that water (fresh or marine), a float-glass side-pane thickness estimate by Stilwell's method, and the '1 inch of fish per gallon' stocking heuristic.","use_when":"You are planning or filling a rectangular aquarium and need its capacity, the load on a stand or floor, a glass-thickness ballpark or a rough stocking limit.","do_not_use_when":"The tank is bow-front, cylindrical or hexagonal (compute the footprint area separately), or you need a swimming-pool volume (use pool-volume).","inputs":[{"name":"length","label":"Length","type":"number","required":true,"max":2000,"exclusive_min":0,"description":"Internal length of the tank.","example":100},{"name":"width","label":"Width (depth front to back)","type":"number","required":true,"max":2000,"exclusive_min":0,"description":"Internal width.","example":40},{"name":"height","label":"Height","type":"number","required":true,"max":2000,"exclusive_min":0,"description":"Internal height (water height when full).","example":50},{"name":"unit","label":"Unit","type":"enum","required":false,"default":"cm","values":[{"value":"cm","label":"centimetres","aliases":["centimeters","centimetres","metric"]},{"value":"in","label":"inches","aliases":["inch","inches","imperial"]}],"description":"Unit of the three dimensions.","example":"cm"},{"name":"fill_percent","label":"Fill level","type":"number","unit":"%","required":false,"default":100,"min":10,"max":100,"description":"Water height as a percentage of the tank height (allow for the air gap and substrate).","example":100}],"outputs":[{"name":"volume_liters","label":"Water volume","type":"number","unit":"L","decimals":1,"description":"length × width × water height."},{"name":"volume_gallons_us","label":"Water volume","type":"number","unit":"US gal","decimals":1,"description":"Same volume in US gallons (3.7854 L)."},{"name":"volume_gallons_uk","label":"Water volume","type":"number","unit":"UK gal","decimals":1,"description":"Same volume in imperial gallons (4.5461 L)."},{"name":"water_weight_kg","label":"Fresh water weight","type":"number","unit":"kg","decimals":1,"description":"Volume × 0.998 kg/L (fresh water at 20 °C), excluding glass, substrate and rock."},{"name":"seawater_weight_kg","label":"Sea water weight","type":"number","unit":"kg","decimals":1,"description":"Volume × 1.025 kg/L for marine tanks."},{"name":"glass_thickness_estimate_mm","label":"Glass thickness estimate","type":"number","unit":"mm","decimals":1,"description":"Side-pane float glass thickness from t = √(β × H³ × 0.00001 / 5.05) with safety factor 3.8 (H = water height in mm)."},{"name":"recommended_glass_mm","label":"Standard glass to use","type":"integer","unit":"mm","decimals":4,"description":"Next standard sheet thickness (4, 5, 6, 8, 10, 12, 15, 19 mm) at or above the estimate."},{"name":"stocking_inches_of_fish","label":"Stocking guideline","type":"number","unit":"inches of fish","decimals":1,"description":"Total adult length of small fish by the 1 inch per US gallon heuristic (rough guide only)."}],"input_schema":{"type":"object","properties":{"length":{"description":"Internal length of the tank.","type":"number","maximum":2000,"exclusiveMinimum":0,"examples":[100]},"width":{"description":"Internal width.","type":"number","maximum":2000,"exclusiveMinimum":0,"examples":[40]},"height":{"description":"Internal height (water height when full).","type":"number","maximum":2000,"exclusiveMinimum":0,"examples":[50]},"unit":{"description":"Unit of the three dimensions.","type":"string","enum":["cm","in"],"default":"cm","examples":["cm"]},"fill_percent":{"description":"Water height as a percentage of the tank height (allow for the air gap and substrate). Unit: %.","type":"number","minimum":10,"maximum":100,"default":100,"examples":[100],"x-unit":"%"}},"additionalProperties":false,"required":["length","width","height"]},"output_schema":{"type":"object","properties":{"volume_liters":{"description":"length × width × water height. Unit: L.","type":"number","x-unit":"L"},"volume_gallons_us":{"description":"Same volume in US gallons (3.7854 L). Unit: US gal.","type":"number","x-unit":"US gal"},"volume_gallons_uk":{"description":"Same volume in imperial gallons (4.5461 L). Unit: UK gal.","type":"number","x-unit":"UK gal"},"water_weight_kg":{"description":"Volume × 0.998 kg/L (fresh water at 20 °C), excluding glass, substrate and rock. Unit: kg.","type":"number","x-unit":"kg"},"seawater_weight_kg":{"description":"Volume × 1.025 kg/L for marine tanks. Unit: kg.","type":"number","x-unit":"kg"},"glass_thickness_estimate_mm":{"description":"Side-pane float glass thickness from t = √(β × H³ × 0.00001 / 5.05) with safety factor 3.8 (H = water height in mm). Unit: mm.","type":"number","x-unit":"mm"},"recommended_glass_mm":{"description":"Next standard sheet thickness (4, 5, 6, 8, 10, 12, 15, 19 mm) at or above the estimate. Unit: mm.","type":"integer","x-unit":"mm"},"stocking_inches_of_fish":{"description":"Total adult length of small fish by the 1 inch per US gallon heuristic (rough guide only). Unit: inches of fish.","type":"number","x-unit":"inches of fish"}}},"formula":"water_height = height × fill_percent / 100; V = length × width × water_height (cm³ / 1000 = L; in³ × 0.016387 = L); US gal = L / 3.785411784; UK gal = L / 4.54609; glass t_mm = √(β × H_mm³ × 0.00001 / 5.05), β by length/height ratio: 0.5 → 0.2419, 1 → 0.294, 1.5 → 0.325, 2 → 0.3415, 2.5 → 0.35, 3 → 0.37 (interpolated, clamped); stocking = US gallons × 1 inch","method":"The glass formula is Warren Stilwell's method for a side pane supported on three edges: allowable stress 5.05 N/mm² (19.2 N/mm² tensile strength of annealed glass ÷ safety factor 3.8) under hydrostatic load. The 1-inch-per-gallon rule ignores fish body mass, activity and filtration and overstocks tanks with fish over about 3 inches; use it only as a first sanity check.","sources":[{"name":"Aquarium World – Calculating glass thickness for aquariums (Stilwell method, β/α tables)","url":"https://aquariumworld.nz/forums/fish/articles-guides/technical-diy/calculating-glass-thickness-for-aquariums-r23/","type":"reference","retrieved_at":"2026-09-24"},{"name":"Fishkeeping – stocking rules of thumb (Wikipedia)","url":"https://en.wikipedia.org/wiki/Fishkeeping","type":"reference","retrieved_at":"2026-09-24"},{"name":"Gallon – US and imperial definitions (Wikipedia)","url":"https://en.wikipedia.org/wiki/Gallon","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"100 × 40 × 50 cm tank","inputs":{"length":100,"width":40,"height":50,"unit":"cm"},"expected":{"volume_liters":200,"volume_gallons_us":52.8,"volume_gallons_uk":44,"water_weight_kg":199.6,"seawater_weight_kg":205,"glass_thickness_estimate_mm":9.2,"recommended_glass_mm":10,"stocking_inches_of_fish":52.8},"url":"https://tttkmbb.com/api/v1/calculate/aquarium-volume?length=100&width=40&height=50&unit=cm"},{"name":"48 × 13 × 21 in ('55 gallon')","inputs":{"length":48,"width":13,"height":21,"unit":"in"},"expected":{"volume_liters":214.7,"volume_gallons_us":56.7,"volume_gallons_uk":47.2,"water_weight_kg":214.3,"glass_thickness_estimate_mm":10.2,"recommended_glass_mm":12},"url":"https://tttkmbb.com/api/v1/calculate/aquarium-volume?length=48&width=13&height=21&unit=in"}],"faq":[{"q":"Why is my '55 gallon' tank only 52 gallons here?","a":"Trade names use nominal external sizes; internal dimensions, the air gap and substrate reduce real water volume by 10–15%. Enter internal measurements and a fill_percent below 100 for the actual amount."},{"q":"Can I rely on the glass thickness estimate?","a":"It is a ballpark for annealed float glass panes with a rim and no bracing; manufacturers often use thinner glass with braces and thicker glass for tanks over 60 cm high. Check with the glass supplier or a dedicated calculator before building."}],"tags":["aquarium volume calculator","fish tank litres","fish tank gallons","aquarium water weight","aquarium glass thickness"],"related":[{"calculator_id":"pool-volume","reason":"Volume and chlorine dose for swimming pools."},{"calculator_id":"rectangular-prism","reason":"Plain box volume and surface area."},{"calculator_id":"volume","reason":"Convert litres, gallons and cubic metres."}],"links":{"html":"https://tttkmbb.com/everyday/aquarium-volume","markdown":"https://tttkmbb.com/everyday/aquarium-volume.md","json":"https://tttkmbb.com/everyday/aquarium-volume.json","api":"https://tttkmbb.com/api/v1/calculate/aquarium-volume","schema":"https://tttkmbb.com/api/v1/calculators/aquarium-volume","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T01:48:19Z"}