30 cube cm Aquarium: Liters, Weight, Heater and Fish

A 30 cube cm tank holds 27 liters brim-full. Set up, it holds about 23 liters (6.1 US gallons) of real water and weighs about 35 kg (75 lb). Every number below is worked out for this exact tank.

Outside size (L × W × H)
30 × 30 × 30 cm11.8 × 11.8 × 11.8 in
Label volume
27 liters7.1 US gallons
Real water, set up
23 liters6.1 US gallons
Empty weight
4 kg10 lb
Filled weight, about
35 kg75 lb
Heater, normal room
50 W

What is a 30 cube cm tank good for?

A 30 cube cm tank holds 27 liters, close to a 5.5 gallon tank in American sizes. It is a nano tank. Small tanks change temperature and water quality fast, so stock lightly and test often.

How much water does it really hold?

The label says 27 liters (7.1 US gallons). 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 30 cube cm tank holds about 23 liters (6.1 US gallons). Use that smaller number when you dose medicine or water conditioner. Work out your exact water volume

How much does a 30 cube cm tank weigh?

An empty glass 30 cube cm tank weighs about 4 kg (10 lb). Filled, with gravel and a few rocks, it weighs about 35 kg (75 lb). That is about as much as a small child, so put it on a sturdy, level surface. The load on the floor under the tank is about 390 kg/m² (79 lb per square foot). 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)25 W
Normal room, 68 °F (20 °C)50 W
Cold room, 63 °F (17 °C)50 W

Check your own room and target temperature

What size filter does it need?

For a community tank, look for a filter rated at 100–150 L/h (20–40 GPH). 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)4 kg8 lb4 kg8 lb
2 in (5 cm)7 kg15 lb8 kg16 lb
3 in (7.5 cm)11 kg23 lb11 kg24 lb

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 6 liters (1.5 US gallons) for this tank. A big clean-up change is half: about 11 liters (3 US gallons). Plan changes from your nitrate reading

How many fish can go in a 30 cube cm 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
Betta11
Cherry shrimpup to 366
Chili rasboraup to 108

Build your own fish list for this tank

Questions and answers

How many liters is a 30 cube cm aquarium?

A 30 cube cm tank is 27 liters brim-full (7 US gallons, 6 UK gallons). Set up, it holds about 23 liters of water.

How much does a 30 cube cm tank weigh?

Empty, about 4 kg (10 lb). Filled with water, gravel and rocks, about 35 kg (75 lb). Add the weight of the stand to find the load on your floor.

What size heater does a 30 cube cm tank need?

In a normal room at 68 °F (20 °C), 50 W holds 78 °F (25.5 °C). In a cold room use 50 W; in a warm room 25 W is enough.

How many fish can I put in a 30 cube cm tank?

It depends on the fish, not just the gallons. As the only kind in the tank, a 30 cube cm tank carries about 1 betta, or 36 cherry shrimp, or 10 chili rasboras. Mixed tanks hold fewer of each.

Other tank sizes

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