20 Gallon Long tank dimensions

76 L (20 gal)76.2 × 30.5 × 30.5 cm (30 × 12 × 12 in)

20 Gallon Long tank dimensions are 76.2 × 30.5 × 30.5 cm (30 × 12 × 12 in). The tank is rated at 76 L (20 gal). Its footprint is 76.2 × 30.5 cm and the water stands about 24.5 cm deep once a 6 cm substrate layer is in — key measurements for choosing plants and livestock.

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At a glance

Size76.2 × 30.5 × 30.5 cm (30 × 12 × 12 in)
Volume76 L (20 gal), as sold
Water after substrateAbout 52 L (14 gal) with a 6 cm substrate layer
Footprint76.2 × 30.5 cm (30 × 12 in)
Water depth24.5 cm (9.6 in)
Substrate neededAbout 14 L for a 6 cm layer

Before it goes in

  • 20 Gallon Long is 76.2 × 30.5 × 30.5 cm (30 × 12 × 12 in) — rated at 76 L (20 gal), and roughly 52 L (14 gal) of actual water once a 6 cm substrate layer and the hardscape are in.
  • That layer takes about 14 L of substrate, which is what you order by.
  • 106 of the 160 animals in this library list a minimum tank at or under 76 L (20 gal). The biggest of them that still fit are Marbled Crayfish and Axolotl. Dwarf Neon Rainbowfish and Hillstream Loach need more than this.
  • The water sits about 24.5 cm (9.6 in) deep over the substrate. Plants that get taller than that — Hygrophila corymbosa 'Siamensis' and Water Sprite — reach the surface and start growing along it, which is a look you either want or trim.
  • Its footprint is 76.2 × 30.5 cm, and that is the area a carpet has to cover — the number that decides how many pots you buy, not the volume.

20 Gallon Long tank dimensions: care and setup

What are the 20 Gallon Long tank dimensions?

20 Gallon Long tank dimensions are 76.2 × 30.5 × 30.5 cm (30 × 12 × 12 in).

How much water does it hold?

It is sold as 76 L (20 gal), and roughly 52 L (14 gal) of actual water once the substrate is in. Stocking works off the second number; minimum-tank-size advice works off the first.

How much substrate does it take?

About 14 L for a 6 cm layer.

What fits in it?

106 of the 160 animals in this library list a minimum tank at or under its volume, and the water depth of about 24.5 cm sets which plants can grow without reaching the surface.

What fits in it

Often compared with

20 Gallon Long20 Gallon High60H Tall
Size76.2 × 30.5 × 30.5 cm61 × 30.5 × 40.6 cm60 × 30 × 45 cm
Volume76 L76 L81 L
Footprint76.2 × 30.5 cm61 × 30.5 cm60 × 30 cm
Water depth24.5 cm34.6 cm39 cm

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