90 Gallon tank dimensions
48×18×24inches
Length × width × height. In metric, 121.9 × 45.7 × 61 cm.
A standard 90 gallon aquarium is 48 inches long, 18 inches front to back and 24 inches tall. Its measurements work out to almost exactly the volume on the label. Once you add gravel and leave a gap at the top, expect a little less water than that.
How much a 90 gallon tank weighs
Empty, the glass tank weighs about 137 pounds. Filled with water and two inches of gravel it comes to roughly 980 pounds, before rocks, wood or equipment.
That is the weight of several people standing in one spot for years. Put it on a purpose-built stand, across the floor joists or near a load-bearing wall, and check an upstairs floor before you fill it.
| Empty tank | about 137 lb |
|---|---|
| Water (90 gallons) | 751 lb |
| Gravel, 2 inches deep | about 93 lb |
| Filled, with gravel | about 980 lb |
| Load on the floor | about 163 lb per sq ft |
Stand, lid, heater and filter sizes
The stand and the lid both follow the footprint, 48 by 18 inches. A stand has to support the whole bottom frame, so it can be bigger than the tank but never smaller.
The 90 gallon has the same 48 x 18 inch footprint as the 60 gallon breeder, 75 gallon, so they share stands and lids.
For a heated tropical tank, a 2 x 200 W heater suits a normal room. Two heaters split the load and fail safer. Pick a filter rated to turn the water over four to six times an hour.
| Footprint | 48 x 18 in (6 sq ft) |
|---|---|
| Volume | 90 gal (340.7 L) |
| Heater | 2 x 200 W |
| Filter flow | 360 to 540 gal per hour |
| Typical glass | about 3/8 in thick |
What fish can live in a 90 gallon tank
How many of each fish would fill this tank on its own. Mix species and the numbers come down, so plan a real community with the calculator.
- Betta1 only
- Neon tetraup to 101
- Ember tetraup to 152
- Guppyup to 50
- Harlequin rasboraup to 67
- Zebra danioup to 60
- Cherry barbup to 60
- Platyup to 60
- Panda coryup to 60
- Bronze coryup to 40
- Honey gouramiup to 6
- Dwarf gourami1 only
- Pearl gouramiup to 4
- Tiger barbup to 50
- Mollyup to 36
- Angelfishup to 6
- Fancy goldfishup to 4
- Bristlenose pleco1 only
- Boeseman's rainbowfishup to 20
- German blue ramup to 2
- Electric yellow labup to 20
- Discusup to 9
- Oscar1 only *
- Common goldfish1 only
* Fits by volume, but the footprint is under what Seriously Fish recommends for the species.

Too big for this tank
- Clown loach needs a bigger tank: the recommended minimum is a 71 x 24 in footprint.
- Common pleco grows too big for this tank.
- Bala shark needs a bigger tank: the recommended minimum is a 94 x 24 in footprint.
Gear for a 90 gallon tank
Searches on Amazon for the right size. Check the tank size or flow rating on the listing before you buy.
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