Every number for a healthier tank
Free fish tank calculators: tank volume is length x width x height in inches divided by 231, a heater needs about 3 to 5 watts per gallon, and most tanks want a 20 to 25 percent water change each week. Get the exact numbers for your aquarium below, freshwater or saltwater.
Length
48 in
Width
18 in
Height
21 in
75 gallons
284 L · ~750 lb filled
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Seachem Prime Water Conditioner
Dechlorinates every refill and detoxifies ammonia and nitrite between water changes.
Check price on Amazon · Under $25
Pawfly 5 in 1 Water Master Test Kit
Liquid tests for pH, ammonia, nitrite, nitrate, and phosphate, the numbers every tank runs on.
Check price on Amazon · Under $50
VEVOR 4-Stage Canister Filter (396 GPH)
Quiet multi-stage canister filtration for 100 to 125 gallon tanks.
Check price on Amazon · Under $100As an Amazon Associate we earn from qualifying purchases. Budget bands come from our catalog; Amazon shows the current price.
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Aquarium Setup & Maintenance Planner
Stocking planner, water-test log, cycling tracker, maintenance schedule, and more, in one printable PDF that keeps your tank on track.
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