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Nestiex

Aquarium Gravel Calculator

Work out how much gravel substrate your aquarium needs. Enter the tank's length, width and your desired gravel depth to estimate the amount to buy.

Aquarium Gravel Calculator

0
lbs of gravel
0
kilograms
0
bags (20 lb)
0
cubic yards
Aquarium Gravel Calculator, live preview
gravel
Enter values to see your estimate.

How to Calculate Aquarium Gravel

Change the calculator above and watch every figure and the diagram below update live.

Top-down view (area × depth)

W L depth 4"

Step 1 · Area

20 ft × 10 ft = 200 ft²

Step 2 · Volume (× depth, ÷ 27)

200 ft² × 0.33 ft ÷ 27 = 2.47 yd³

3.46
tons (× 1.4)
134
bags (÷ 0.5 ft³)

These figures update automatically as you change the calculator above.

Aquarium gravel depth guide

Approximate coverage of one cubic yard of gravel at common depths.

Approximate coverage of one cubic yard of gravel at common depths.
DepthCoverage per yd³Relative coverage
1" 324 sq ft
100%
2" 162 sq ft
50%
3" 108 sq ft
33%
4" 81 sq ft
25%
6" 54 sq ft
17%
3 in
3"

At 3 inches deep, one cubic yard of gravel covers 108 sq ft.

Aquarium Gravel FAQs

How much gravel do I need for my fish tank?
Multiply the tank's length × width (in feet) by your gravel depth, then convert. A common rule is about 1–1.5 lbs of gravel per gallon of water.
How deep should aquarium gravel be?
Use about 1–2 inches for most tanks, or 2–3 inches if you keep live rooted plants that need anchoring.
How do I convert tank size to gravel amount?
Enter the tank footprint and depth here for a volume estimate, then round up so you can rinse and discard fines before adding it.
Is gravel or sand better for a fish tank?
Both work, gravel allows better water flow to the substrate, while sand suits bottom-dwelling species. This tool estimates volume for either.

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