How to Set up an Aquarium CO2 System The Easy Way


How to Set Up an Aquarium CO2 System the Easy Way

We encourage newbies to plant tanks with slow-growing plants. They only require low light and an all-in one fertilizer. Certain plants can be difficult to grow underwater. They may need more carbon dioxide (CO2) than what is naturally present in the air. Aquarists can inject CO2 gas directly into water using many methods. They have tried many types of equipment, scheduling and dosage amounts. Aquarium Co-Op has tested many of them, and this is our preferred method. It’s reliable and simple to use.

Does CO2 get rid of algae? It’s a common belief that CO2 automatically fixes algae problems, but this is not true. A healthy planted tank must have three components in balance – lighting, fertilizer, and carbon dioxide. CO2 is not the only primary ingredient that plants need in order to grow. Too much light and fertilizer is common among beginners. Adding CO2 to the aquarium can balance it. If a tank is over-lit or has too little fertilizer but not enough CO2 injection, algae can form.

Let’s use a cookie recipe as an analogy. To make a larger batch of cookies (e.g. greater plant growth), you should add 5x the normal amount of flour (e.g. fertilizer), to your dough. You can make a bad cookie if you only add 5x as much flour to your recipe.

Do all aquarium plants need CO2 injection? As mentioned before, all aquatic plants use CO2 as one of their basic building blocks. Cryptocoryne plants are one example of a type that doesn’t require extra CO2, but other types such as scarlet temple, which could benefit from it, don’t. A third category of plants – which includes Blyxa japonica, dwarf hairgrass, and dwarf baby tears and other similar carpeting plants – has higher demands and necessitates the use of CO2 for the best chances of success.

Materials for a CO2 Systems

We will be focusing on the installation and operation of the CO2 system. To get started, gather the necessary equipment and tools:

1. Aquarium Co-Op CO2 regulator – What is a regulator? A regulator is a device that allows you to precisely control how much gas exits the CO2 cylinder tank and enters the aquarium water. – What is the difference between a single-stage vs. two-stage regulator? A single-stage regulator reduces the cylinder’s gas pressure in one step, whereas a two-stage regulator reduces the pressure in two steps, resulting in a more stable and reliable flow of CO2. Two-stage regulators are also better at preventing “end-of tank dumps,” where a CO2 cylinder that is nearly empty may leak its remaining gas in one step. Which CO2 system should I choose? While DIY systems are cheaper than pressurized systems, they don’t have the same stability as a CO2 system that uses a regulator and/or cylinder. DIY reactions produce lots of CO2 initially, then slowly decrease in quality over time. This can make it difficult to balance a plant tank. The process can be slow and difficult to maintain because the pressure is lower, the temperature can influence the reaction, as well as the time it takes. We can set it up once, and it will run for one- to three years before we have to refill it.

1. Aquarium Co-Op manifold add-ons – You can add up to five additional manifold blocks to your regulator to expand the system or run CO2 to multiple tanks.

1. CO2 cylinder tanks – Is it possible to use a CO2 paintball tank? They work with standard cylinder tanks that have the male thread size CGA320. I need a CO2 tank. We buy ours from local welding supply and home brewing stores. Usually, they also offer CO2 refill services if you bring back your cylinder when it’s empty. Which size CO2 cylinder should you get? For high-tech planted aquariums that use high levels of CO2, it is recommended to get the largest size cylinder possible. This will allow you to not need to refill the cylinder as often. However, for the average customer, we often suggest a 2.5-5 lb. cylinder for 20-gallon aquariums or smaller, a 5 lb. A 10 lb. cylinder is available for 25-to-40-gallon aquariums. cylinder for 55-gallon aquariums or larger. If you plan on using one regulator with five or six aquariums, then scale the cylinder size accordingly.

1. Airline tubing, or CO2 tubing, is it necessary? We have never seen any CO2 loss in our aquariums using the Aquarium Co-Op airline tube (a flexible, black, PVC-based tubing) from Aquarium Co-Op. In our experience, special CO2 tubing is more expensive, harder to bend, and not as readily available.

1. Regular check valve or stainless steel check valve (optional) – Do I need a check valve for my CO2 system? Check valves are used to prevent water from flowing out of the aquarium and pouring all over the regulator when it is turned off. The bubble counter in the Aquarium Co-Op regulator comes with a built-in check valve, but you can install a second one as backup if desired. We have personally used the regular plastic check valves with CO2 systems at our fish store, warehouse, and homes, and they have not broken down. However, plastic can be degraded by CO2 over time so we offer stainless steel versions for better durability.

1. CO2 diffuser – Which type of diffuser should I get? Any CO2 diffuser intended for aquariums that can operate at approximately 40-50 psi should be fine. How can I clean a blocked CO2 diffuser? Algae buildup must be removed from the diffusers. Because diffusers can be made of different materials, follow the manufacturer’s cleaning instructions to use diluted bleach, vinegar, or other methods.

1. Mineral oil or water – You can use regular tap water to fill the bubble count so you can determine the rate at which CO2 enters the aquarium. Mineral oil can be used in place of water, as the water will evaporate.

Timer for electrical outlets 1. Adjustable wrench of at least 1.25 inches width Scissors Spray bottle with water and a few drops of Dawn dish soap

How to Install a CO2 System

Once you have the necessary equipment, we recommend that you read our detailed manual and watch the video tutorial to learn how to use it. This high-level diagram will help you see the whole CO2 system.

The regulator (B), screws onto the CO2 tank (A). The regulator (B), can be upgraded with optional manifold block add ons. – The bubble counter (C) on the regulator is filled with liquid, and airline tubing is attached to the lid of the bubble counter. The airline tubing connects with the diffuser (D), which can be found at the bottom. The optional check valve, (E), is installed along with the airline tubing at the aquarium rim. The regulator’s solenoid vale cable (F), is connected to the adapter (G). The power adapter (G), plugs into the electrical outlet (H), which plugs into either a wall outlet, or power strip.

What if the CO2 bubbles emitted from the diffuser get into the aquarium’s water surface? This is normal. Your diffuser should be placed as low as possible within the aquarium. As the bubbles rise from the diffuser, you can see them becoming smaller and smaller. The CO2 gas is being absorbed by the water.

Place the diffuser at the base of the aquarium to give the CO2 bubbles a longer time to dissolve into the water.

How Much CO2 to Dose

In the manual, we recommend tuning the regulator to approximately 1 bubble per second (i.e., the rate of CO2 bubbles flowing through the bubble counter) because we would rather start with a lighter amount of CO2 to keep the fish safe. That being said, CO2 dosing amounts are different for every tank, and the bubble rate is not a perfect form of measurement since each aquarium has different plant and fish stocking levels. We don’t use drop-checkers to find the perfect CO2 level, but we trust the plants and nature to tell us when they’re happy.

When the plants photosynthesizing during the daytime, they consume carbon dioxide and produce oxygen (O2) and sugars as a byproduct.

If plants have enough carbon dioxide and light, they can produce enough oxygen to saturate the water. This is visible as small bubbles appearing from the leaves. In our warehouse, we dial the CO2 level on our plant-holding aquariums until we consistently see this “pearling” effect. Plants are living things and it takes around 24 hours for any CO2 adjustment to have an effect. We like to wait three days before we make the next change.

When the water is saturated in oxygen, aquatic plants produce visible bubbles.

When should I turn on and off the CO2 in my aquarium? As mentioned before, plants use CO2 when there is light to photosynthesize. However, the process reverses at night and becomes the respiration cycle, in which plants consume oxygen and sugars and release CO2. Therefore, we want to shut off the CO2 regulator when the aquarium light is off. To optimize CO2 use, set the regulator’s timer so that it turns on about 1-2 hours before the aquarium light comes on. The regulator will then turn off approximately 1 hour before the light goes out. (If you only have one timer, you can use the same timer with a power strip so that the light and regulator turn on and off at the same time.)

Is CO2 dangerous for aquarium fish? It can be harmful for animals in large enough quantities if (1) CO2 causes the water pH to drop too quickly or (2) people try to be so efficient with the CO2 that they end up cutting off the oxygen that fish need to breathe. In the latter case, some hobbyists try to minimize surface agitation so that less gas exchange occurs and less CO2 escapes the water. However, less gas exchange also means less oxygen will enter the water, which can cause your fish to struggle and gasp for air. We recommend increasing both O2 and CO2 in the water using an airstone (or any other device that agitates water) along with your pressurized carbon dioxide system. Yes, you may have to increase your bubble rate a little to compensate for the slight loss of CO2, but having enough oxygen for your fish (and plants at night) is more important and can help lead to the pearling effect that is so desired by planted tank enthusiasts.

We wish you the best with your new pressurized carbon dioxide system. We hope you have lots of fun exploring high-tech plants. For more information on our CO2 regulator, check out the product page for the official manual, demo video, and more.