How to use it
- Enter tank length in centimeters.
- Enter tank width in centimeters.
- Enter desired gravel depth in centimeters.
- Read the liters result and buy that amount of gravel.
What it does – The Aquarium Gravel Calculator turns your tank dimensions and chosen gravel depth into a single volume number expressed in liters. Knowing the exact liter amount lets you purchase the right amount of substrate the first time, avoiding costly over‑buy or under‑fill that can affect water chemistry and plant health. Why it matters – Too little gravel reduces beneficial bacteria surface, while too much raises maintenance and cost. How to read it – The result shows the total gravel volume; round up a little to allow for compaction and spillage, then order that many liters of gravel. Different gravel types settle at different rates, so after you have the base liter figure, add 5‑10% for coarse stones or for a thicker layer you plan to keep. The calculator works for rectangular tanks; for bow‑front or cylindrical tanks break the shape into measurable rectangles and sum them.
Pro tips
- Add 10% extra volume to cover compaction and spillage.
- Round up to the nearest whole liter when ordering.
- If gravel is sold by weight, check density and convert to liters.
- Measure depth after a small test fill to avoid over‑estimating.
Real-life examples
- Planning a new 120 cm long community tank and need exact substrate amount.
- Refilling a planted tank after a water change and want to match the original gravel depth.
- Comparing prices between suppliers by converting their offerings to liters.
Case study
Sam measured his 90 cm × 45 cm tank, entered a 5 cm gravel depth, and got 20.3 L. He ordered 21 L, saved a $15 over‑buy, and his new plants thrived with stable bacteria colonies.