Aquarium guides, straight to the point.
Every guide below pairs real keeper experience with a free calculator, so you can read the reasoning and then run the numbers on your own tank.
How Many Gallons Is My Tank?
Measure any standard or custom aquarium, separate real water volume from the number on the box, and understand why the difference matters for dosing, stocking, and equipment.
How Many Fish Can I Keep?
A practical look at the one-inch-per-gallon rule, adult sizing, schooling behaviour, and realistic stocking plans for 20, 30, and 55 gallon community tanks.
How Much Does an Aquarium Weigh?
Water, glass, substrate, and equipment add up faster than expected. Estimate a filled tank's total weight and check whether your floor and stand can safely carry it.
CO₂ Injection Guide for Planted Tanks
Why 30 ppm is the planted-tank benchmark, how the pH and dKH relationship works, and how to read a drop checker without stressing your fish.
Standard Aquarium Tank Sizes
Reference table of standard aquarium sizes from 5 to 125 gallons, with typical dimensions, real water volume, and filled weight estimates for planning.
How Much Substrate Do I Need?
Depth targets for fish-only and planted setups, gravel versus sand versus aqua-soil density, and converting a bed depth into the bags you'll actually buy.
Still need the tool, not the theory?
Jump straight into any of the eight calculators.