20 gallon long vs 20 gallon high
Both hold 20 gallons. The long is 30 x 12 x 12 inches and the high is 24 x 12 x 16. For most fish the long is the better tank, because fish use length, not height.
20 Gallon Long
20 Gallon High
Side by side
| 20 Gallon Long | 20 Gallon High | |
|---|---|---|
| Dimensions (L x W x H) | 30 x 12 x 12 in | 24 x 12 x 16 in |
| Footprint | 2.5 sq ft | 2 sq ft |
| Water, to the brim | 18.7 gal | 19.9 gal |
| Empty weight | about 23 lb | about 24 lb |
| Filled, with gravel | about 229 lb | about 222 lb |
| Floor load | about 92 lb/sq ft | about 111 lb/sq ft |
| Heater | 100 W | 100 W |
| Filter flow | 80 to 120 gph | 80 to 120 gph |
| Stand and lid | 30 x 12 in | 24 x 12 in |
Pick the 20 gallon long if
- You keep schooling fish, corydoras or a betta. Swimming room and floor space matter more than height.
- You want the tank on a desk or low stand. It is only 12 inches tall.
- You plan to scape it: the 30 inch length gives more room to work with.
Pick the 20 gallon high if
- You are short on floor space. It takes the 24 x 12 inch spot of a 15 gallon.
- You keep fish that use height, such as dwarf gouramis or a tall plant layout.
- You already own a 24 inch stand or lid.
What fits in one but not the other
Every popular fish we checked that fits the 20 gallon high also fits the 20 gallon long.
From the popular fish we checked against the Seriously Fish footprints.
More of the same fish
| 20 Gallon Long | 20 Gallon High | |
|---|---|---|
| Neon tetra | 21 | 22 |
| Ember tetra | 31 | 33 |
| Guppy | 10 | 11 |
| Harlequin rasbora | 14 | 15 |
| Cherry barb | 12 | 13 |
| Platy | 12 | 13 |
Mixes that work in the 20 gallon long
- Neon tetras and panda corydoras95% stocked
10 × Neon tetra, 6 × Panda cory.
- A betta with a school of harlequin rasboras68% stocked
1 × Betta, 8 × Harlequin rasbora.
- A school of zebra danios63% stocked
8 × Zebra danio. This tank is under the recommended minimum for Zebra danio (a 35 x 12 in footprint).
- Cherry barbs and panda corydoras95% stocked
6 × Cherry barb, 6 × Panda cory.
Mixes that work in the 20 gallon high
- Neon tetras and panda corydoras89% stocked
10 × Neon tetra, 6 × Panda cory.
- Ember tetras and pygmy corydoras56% stocked
10 × Ember tetra, 6 × Pygmy cory.
Common questions
Which is bigger, a 20 gallon long or a 20 gallon high?
They hold about the same water: 18.7 gallons to the brim for the 20 gallon long and 19.9 for the 20 gallon high. The difference is the shape. The 20 gallon long is 30 x 12 inches on the floor and 12 tall; the 20 gallon high is 24 x 12 and 16 tall.
Do a 20 gallon long and a 20 gallon high use the same stand?
No. The 20 gallon long needs a 30 x 12 inch stand and the 20 gallon high a 24 x 12 inch one.
Which weighs more, a 20 gallon long or a 20 gallon high?
About the same: roughly 229 lb for the 20 gallon long and 222 lb for the 20 gallon high, filled with water and two inches of gravel. The 20 gallon high puts 111 lb per square foot on the floor against 92, because the same weight sits on a smaller footprint.
Is a 20 gallon long better than a 20 gallon high?
For most fish, yes. Schooling fish and bottom dwellers use the extra 6 inches of length, and the lower height is easier to light and plant. The high suits a tight space or fish that use height.
Gear that fits either tank
Heater and filter are the same for both. Stands and lids follow the footprint, so see the 20 gallon long and 20 gallon high pages for those.
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