CO2 for the aquarium

Many aquarists dream of a beautiful, densely planted aquarium that resembles a piece of underwater forest. However, plants often grow slowly and look pale or stunted, despite good lighting and fertilizers. This is where a carbon dioxide, or CO2, supply system comes in handy.

CO2 is to plants what oxygen is to us. It is the main building block in the process of photosynthesis. In a typical aquarium, there is often not enough of it, especially if there are many plants and few fish. Adding CO2 solves this problem, giving plants a powerful boost for growth.

The results of the CO2 system are visible almost immediately. Plants begin to actively sprout new shoots, their leaves become larger and take on lush, bright colors. Many species that previously just survived begin to grow vigorously. This is a key element in creating a truly vibrant and healthy underwater garden.

Why carbon dioxide is needed in an aquarium

The main reason for adding CO to an aquarium₂, – is the supply of nutrients for aquatic vegetation. In ordinary home tanks, the concentration of carbon dioxide reaches 30 mg per 1 liter of water.

A certain percentage of carbon dioxide enters the aquarium water as a result of the vital activity of fish, but this amount is not enough for the full existence of plants. Without a regular supply of carbon, the formation of energy in the process of photosynthesis ceases in plant tissues.

Adding carbon dioxide (CO2) to the aquarium helps plants grow faster and look better — they become brighter, denser, and more resistant to algae. Without sufficient CO2, even with good light and soil, plants will be sluggish and poorly developed. CO2 can be supplied in various ways — from simple homemade systems to ready-made cylinders. The main thing is not to overdo it so as not to harm the fish. Everything works in moderate doses: just a little more air, which is already needed by the green inhabitants of the aquarium.

Methods of saturating water with carbon dioxide

There are several options for supplying carbon dioxide:

• Cylinder installation;
• Braga;
• Chemical reactions with acids;
• Carbon-containing preparations;
• Use of carbonated water.

Cylinder installation

This is the most convenient and correct way to supply gas to water. It is optimal for use in a large general aquarium.

The system includes a cylinder and a reducer consisting of:

• Valves for fine adjustment of the gas supply rate;
• Solenoid valve with coil;
• A safety pressure relief valve;
• Pressure gauges for monitoring pressure;
• Bubble counter.

You can buy the device at a pet store. The cost depends on the manufacturer and refill options: a disposable cylinder costs about 15,000 rubles, while a refillable one will set you back 20,000-50,000 rubles.

The advantage of a generator is precise control of the CO output concentration.₂. The disadvantage is that it is difficult to assemble.

The cylinder is pressurized. How to use it correctly:

• Do not drop.
• Store in a ventilated room away from sources of heat and fire;
• Do not leave in direct sunlight or in a place where the temperature exceeds +50°C;
• Operate in an upright position;
• Refuel at specially designated stations;
• Do not inhale the gas.

Mash

Such a source of CO₂ at home involves a hermetically sealed container with a tube attached to it. Inside is the mash.

Instructions for use: for 1 liter of water in a 2-liter container, take 300 g of sugar and 0.3 g of dry yeast. Sometimes a second container is connected to prevent the foamy mash from entering the aquarium water. Baking soda, gelatin, or starch are used to prolong fermentation. But even so, the device does not work for more than 2 weeks: after processing the sugar, the yeast dies from the alcohol that has formed. You have to disassemble the structure, clean it, and refill it.

The advantages of this device are that it is easy to assemble and safe to use. The disadvantages are that the release of carbon dioxide is unstable and uncontrollable.

Chemical reactions

A less common method of saturating water with CO₂, – conducting a chemical reaction between carbonate products (soda, chalk, eggshells, dolomite) and acid (citric, acetic). To control the amount of carbon dioxide released, the process is carried out in a Kipp laboratory apparatus.

The advantage of this method is its cost-effectiveness. The disadvantages are the same as with mash: problematic regulation of gas formation, the need to renew reagents. It is necessary to install a protective device, since the carbon dioxide formed takes acid particles with it, creating a risk of poisoning the inhabitants of the tank.

Carbon-containing preparations

There are liquid ones (for example, Tetra CO₂ Plus) or in the form of soluble tablets (Hobby Sanoplant CO₂) containing calcium carbonate and organic acid. The principle of operation is simple: when placed in aquarium water, the tablet slowly dissolves, releasing carbon dioxide. But the downside is that the dosage of the preparation has to be determined by eye, and it is not always accurate.

Sparkling water

To enrich a small aquarium (up to 20 liters) with carbon dioxide, you can add regular mineral-free sparkling water daily. For a 10-liter tank, 20 ml of liquid is sufficient.

Devices for supplying carbon dioxide to water

In addition to the CO₂, a special spray unit is required for the aquarium. Its purpose is to prevent carbon dioxide from escaping from the water into the surrounding air. A conventional sprayer from an aeration system will not suffice. A special device called a CO₂. It can be:

1. A glass diffuser that is built into the tank fittings. It goes well with a cylinder system and the carbonate-acid method.
2. Bell cap.
3. Pebble diffuser. Produces large bubbles.
4. Bubble ladder. How it works: in a glass or plastic maze, a gas bubble slowly rises along a winding path, dissolving in the water.
5. Rowan branches. They provide small bubbles. However, contaminated material must be changed regularly.

As you can see, adding carbon dioxide to an aquarium is not just a fad, but an effective tool for creating a truly thriving underwater garden. It is the key to bright colors, rapid growth, and the health of your plants, which ultimately forms a sustainable and beautiful ecosystem.

Of course, the CO2 system requires some attention and understanding of the basics. It is important to start small, choose the right equipment, and remember to monitor the gas supply level. But don't be afraid of this — many aquarists successfully master this process.

In the end, the effort is well worth it. You will get not just an aquarium, but a living, dynamic picture that will delight the eye every day. Watching plants actively grow and fill the space with life is a real reward for any lover of the underwater world.