37 Gallon Fish Tank: Dimensions, Weight, Heater and Fish

A standard 37 gallon tank measures 30 × 12 × 22 inches (76 × 30 × 56 cm). Set up, it holds about 31 gallons (119 liters) of real water and weighs about 380 lb (170 kg). Every number below is worked out for this exact tank.

Outside size (L × W × H)
30 × 12 × 22 in76 × 30 × 56 cm
Label volume
37 gallons140 liters
Real water, set up
31 gallons119 liters
Empty weight
60 lb30 kg
Filled weight, about
380 lb170 kg
Heater, normal room
200 W

What is a 37 gallon tank good for?

The 37 gallon is a tall tank on a 30 inch footprint. The height shows off tall plants and makes a striking display. It does not add swimming length, so stock it like a 29.

How much water does it really hold?

The label says 37 gallons (140 liters). That is the tank filled to the very brim, measured from outside the glass. In real life the glass, the gap at the top, the gravel and the decor take up room. A set-up 37 gallon tank holds about 31 gallons (119 liters). Use that smaller number when you dose medicine or water conditioner. Work out your exact water volume

How much does a 37 gallon tank weigh?

An empty glass 37 gallon tank weighs about 60 lb (30 kg). Filled, with gravel and a few rocks, it weighs about 380 lb (170 kg). That is as much as two or three adults, so use a stand made for aquariums, not ordinary furniture. The load on the floor under the tank is about 151 lb per square foot (740 kg/m²). Add your own stand and rocks

What size heater does it need?

The colder your room, the bigger the heater. These sizes hold the water at 78 °F (25.5 °C), right for most tropical fish.

Your roomHeater to buy
Warm room, 73 °F (23 °C)100 W
Normal room, 68 °F (20 °C)200 W
Cold room, 63 °F (17 °C)250 W

Check your own room and target temperature

What size filter does it need?

For a community tank, look for a filter rated at 130–190 GPH (500–700 L/h). That moves all the water through the filter four to six times an hour. Goldfish and big cichlids need more. Size a filter for your kind of tank

How much gravel or sand?

DepthGravelSand
1 in (2.5 cm)20 lb9 kg21 lb10 kg
2 in (5 cm)39 lb18 kg41 lb19 kg
3 in (7.5 cm)58 lb27 kg62 lb28 kg

Two inches suits most tanks. Rooted plants like three. Work it out in bags

How much water to change

A normal weekly water change is a quarter of the water: about 7.9 gallons (30 liters) for this tank. A big clean-up change is half: about 15.7 gallons (60 liters). Plan changes from your nitrate reading

How many fish can go in a 37 gallon tank?

It depends on which fish. The table shows how many of each the tank carries comfortably if that fish is the only kind in the tank. If you mix kinds, keep fewer of each.

FishHow manyKeep at least
Neon tetraup to 306
Guppyup to 163
Bronze corydorasup to 136
Mollyup to 63
Tiger barbup to 128
Pearl gouramiup to 21
Bristlenose plecoup to 21
Dwarf neon rainbowfishup to 146
Fancy goldfish11
Yellow labup to 64

Build your own fish list for this tank

Fish that need a bigger tank

These fish are often sold for tanks this size, but they outgrow it:

  • Common goldfish: grows to 12 in (30 cm) and needs at least 75 gallons (284 liters).
  • Oscar: grows to 12 in (30 cm) and needs at least 75 gallons (284 liters).
  • Common pleco: grows to 16 in (40 cm) and needs at least 150 gallons (570 liters).
  • Bala shark: grows to 14 in (35 cm) and needs at least 150 gallons (570 liters).

Questions and answers

What are the dimensions of a 37 gallon tank?

A standard 37 gallon glass tank is 30 × 12 × 22 inches (76 × 30 × 56 cm), measured on the outside as length × width × height. Brands differ by up to half an inch.

How much does a 37 gallon tank weigh?

Empty, about 60 lb (30 kg). Filled with water, gravel and rocks, about 380 lb (170 kg). Add the weight of the stand to find the load on your floor.

What size heater does a 37 gallon tank need?

In a normal room at 68 °F (20 °C), 200 W holds 78 °F (25.5 °C). In a cold room use 250 W; in a warm room 100 W is enough.

How many fish can I put in a 37 gallon tank?

It depends on the fish, not just the gallons. As the only kind in the tank, a 37 gallon tank carries about 30 neon tetras, or 16 guppies, or 13 bronze corydoras. Mixed tanks hold fewer of each.

How many liters is a 37 gallon tank?

37 US gallons is 140 liters. Once set up with gravel and decor, the tank holds about 119 liters (31 gallons) of water.

Other tank sizes

Dimensions are the common North American and European standard sizes; brands differ slightly. Weights assume standard glass of typical thickness, 4 cm of gravel and light rockwork. How we calculate