What is a 2.5 gallon tank good for?
A 2.5 gallon tank is a desk tank for shrimp, snails and plants. It is too small for fish, a betta included: so little water heats up, cools down and turns dirty very fast.
How much water does it really hold?
The label says 2.5 gallons (9 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 2.5 gallon tank holds about 2.1 gallons (8 liters). Use that smaller number when you dose medicine or water conditioner. Work out your exact water volume
How much does a 2.5 gallon tank weigh?
An empty glass 2.5 gallon tank weighs about 5 lb (2 kg). Filled, with gravel and a few rocks, it weighs about 30 lb (14 kg). 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 61 lb per square foot (300 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 room | Heater to buy |
|---|---|
| Warm room, 73 °F (23 °C) | 10 W |
| Normal room, 68 °F (20 °C) | 25 W |
| Cold room, 63 °F (17 °C) | 25 W |
Check your own room and target temperature
What size filter does it need?
For a community tank, look for a filter rated at 10–10 GPH (50–50 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?
| Depth | Gravel | Sand |
|---|---|---|
| 1 in (2.5 cm) | 4 lb2 kg | 5 lb2 kg |
| 2 in (5 cm) | 8 lb4 kg | 9 lb4 kg |
| 3 in (7.5 cm) | 12 lb6 kg | 13 lb6 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 0.5 gallons (2 liters) for this tank. A big clean-up change is half: about 1.1 gallons (4 liters). Plan changes from your nitrate reading
How many fish can go in a 2.5 gallon tank?
None. A 2.5 gallon tank is too small for fish to live well. It makes a lovely home for cherry shrimp, a nerite snail and live plants.
Questions and answers
What are the dimensions of a 2.5 gallon tank?
A standard 2.5 gallon glass tank is 12 × 6 × 8 inches (30 × 15 × 20 cm), measured on the outside as length × width × height. Brands differ by up to half an inch.
How much does a 2.5 gallon tank weigh?
Empty, about 5 lb (2 kg). Filled with water, gravel and rocks, about 30 lb (14 kg). Add the weight of the stand to find the load on your floor.
What size heater does a 2.5 gallon tank need?
In a normal room at 68 °F (20 °C), 25 W holds 78 °F (25.5 °C). In a cold room use 25 W; in a warm room 10 W is enough.
How many fish can I put in a 2.5 gallon tank?
A 2.5 gallon tank is too small for fish. Keep shrimp, snails and plants in it instead.
How many liters is a 2.5 gallon tank?
2.5 US gallons is 9 liters. Once set up with gravel and decor, the tank holds about 8 liters (2 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