Aquarium Tools
Tank volume & weight
Volume uses inside dimensions (subtract glass thickness). Weight = water (1 kg/L) + estimated empty-glass weight. Useful when choosing a stand.
Stocking load checker
Uses the simple "1 cm of fish per litre" rule for tropical community tanks. It ignores species temperament and bioload differences — a guideline, not a law.
Substrate calculator
Estimates dry substrate volume and weight from footprint and depth. A 4–6 cm layer suits most plants; carpets and root feeders like more.
Water-change planner (nitrate)
How much water to replace to dilute nitrate toward your target. Assumes fresh water has 0 ppm nitrate.
Planted-tank CO₂ estimator
Rough estimate from the pH/KH relationship: CO₂ (ppm) ≈ 3 × KH × 10^(7−pH). A drop-checker reading of ~30 ppm (green) is the common planted-tank target.
Heater wattage estimator
Rule of thumb: about 0.5 W per litre for a lidded tank in a normal room, plus extra when the room is cold or the tank is open. Oversizing slightly is safer than undersizing.
Fishless-cycle ammonia doser
Dose of liquid ammonia to reach your target. Assumes 1 mL of a 10% solution adds ~10 mg of NH₃ per mL. Confirm with a test kit before adding livestock.