How to Set Up a Co2 Aquarium System

Written by krina chires
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A CO2 aquarium is ideal for a freshwater fish tank containing many plants. Carbon dioxide is necessary for plants to breathe, so a CO2 tank is efficient because it stabilises CO2 levels in the tank. The CO2 aquarium system will help regulate CO2 properly to keep both plants and fish comfortable. When you buy a CO2 aquarium system, you may choose to have an expert install it, or you can set it up yourself.

Skill level:

Things you need

  • Adjustable wrench
  • Scissors
  • Tape measure
  • 2.27kg. CO2 bottle
  • CO2 regulator
  • Plastic washer
  • Bubble counter with built-in check valve
  • 20 feet of silicone CO2 tubing
  • Compression nut
  • CO2 reactor
  • 10 feet of 1/2-inch flexible tubing
  • Overflow/return spout
  • Maxi-Jet 1200 submersible pump & powerhead
  • 1/2-inch ball valve
  • 6 1/2-inch plastic clamps

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  1. 1

    Procure a five-pound CO2 bottle. A CO2 bottle can be purchased from a welding supply company. If you do not know of any, you can ask your local fire brigade for information on how to obtain a CO2 bottle. They are fairly expensive with prices ranging from £32 to £58.

  2. 2

    Attach the CO2 regulator to the bottle. To do this, first install a plastic washer on the bottle before attaching the regulator. The plastic washer will prevent leaking. Attach the CO2 regulator to the bottle as tightly as you can. The regulator will be twisted clockwise to the bottle's nozzle.

  3. 3

    Move the needle valve clockwise to the "Off" position.

  4. 4

    Open the bubble counter by carefully unscrewing its cap clockwise. Fill the bubble counter with fresh water about 1/3 of the way up. Make sure the open end of the bubble counter is under water. Keep the bubble counter O-ring and the top of the large counter tube dry when you put the top back on the tube. This will ensure the CO2 is tight.

  5. 5

    Attach the bubble counter to the bubble counter mounting bracket on the side of the aquarium. This is done by screwing the bubble counter to the bubble counter mounting bracket located on the right side of the aquarium.

  6. 6

    Attach the CO2 bottle to the bubble counter using silicone tubing. Measure the distance between the CO2 bottle and the bubble counter. Add three inches to the length. Use this number as the length of tubing you will use to connect the bubble counter and CO2 bottle. The extra three inches will make sure the connecting tube will fit properly. To connect one end of the tubing to the CO2 needle valve, remove the compression nut (the cap over the valve). Then put the tube through the nut and over the valve.

  7. 7

    Slide the compression nut over the tube surrounding the valve and tighten securely around the tube and valve. Connect the other side of the tube to the bubble counter. To do this, slide the end of the tube over the shorter of the two nozzles on the bubble counter.

  8. 8

    Cut another tube around the same length as the first. This tube will be used to connect the bubble counter to the CO2 reactor. Attach one side of the tube to the output valve or the longer of the two nozzles on the bubble counter. Attach the other end to the CO2 reactor.

  9. 9

    Cut out another piece of tubing 1/2 inch in order to connect the reactor to the Maxi-Jet Powerhead obtained from your local store. They cost around £16. Make sure the Powerhead and pump are completely under water before you attach it to the reactor. Connect one end to the top of the CO2 reactor and the other end to the Maxi-Jet Powerhead. Tighten each connection with a clamp to make the connections stay put.

  10. 10

    Use the leftover tubing and clamps to connect the reactor, ball valve and the return spout. Put the return spout over the edge of the aquarium. Attach one end of tubing to the output on the bottom of the return spout. Clamp this connection. Connect the other end to one side of the ball valve. Clamp this connection. Using the last of the tubing, connect one end to the other side of the ball valve. Attach the other end to the return spout.

Tips and warnings

  • Make sure all of your connections are as secure as possible to prevent leaking.

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