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Bio-CO2 Pro

What are the advantages of Fluval Bio-CO2 Pro?

Fluval Bio-CO2 Pro combines the safety of biological carbon dioxide production with the convenience of pressurized delivery. With reliable, controllable, low-pressure operation, it is the most secure, simple and environmentally sustainable CO2 delivery system available.

What is the difference between Fluval Bio-CO2 Pro and citric acid systems?

Fluval Bio-CO2 Pro operates at a lower – and therefore safer – pressure than citric acid systems, and functions via a natural, environmentally-friendly biological process as opposed to a chemical reaction with hazardous ingredients.

I am starting to inject CO2 into my aquarium. Should I remove the carbon from my filter?

Yes! Activated carbon can remove trapped gasses, including carbon dioxide.

Why do I have to wait 24 hours after adding the ingredients to turn on my Bio-CO2 Pro system?

It’s important to wait 24 hours after adding the ingredients to your Bio-CO2 Pro system in order to allow the fermentation reaction to occur, which increases the pressure inside the reaction chamber and allows CO2 to reach your aquarium.

How much table sugar should I add to my Bio-CO2 Pro system?

Bio-CO2 Pro 125: add 1 cup / 240 g of table sugar
Bio-CO2 Pro 250: add 2 cups / 480 g of table sugar
Bio-CO2 Pro 500: add 4 cups / 960 g of table sugar
Note that a Bio-CO2 Refill Pack holds exactly one cup of table sugar.

How many Activator yeast sachets and Booster tablets should I use in my Bio-CO2 Pro system?

Bio-CO2 Pro 125: add 1 Activator yeast sachet and 1 Booster tablet
Bio-CO2 Pro 250: add 2 Activator yeast sachets and 2 Booster tablets
Bio-CO2 Pro 500: add 4 Activator yeast sachets and 4 Booster tablets

Can I use more Activator yeast sachets and Booster tablets in my Bio-CO2 Pro system than recommended?

We do not recommend overdosing your Bio-CO2 Pro system. Doing so will result in a more intense reaction which could cause the reaction chamber to overflow. The quantities of each ingredient have been carefully measured to ensure effective and long-lasting  CO2 production, and should therefore be adhered to.

Can I use any kind of yeast in my Bio-CO2 Pro system?

Bio-CO2 Pro Activator yeast is professionally crafted for rapid-start fermentation and maximum CO2 production. We do not recommend the use of other types of yeast.

What is the shelf life of Bio-CO2 Pro Activator yeast sachets?

Bio-CO2 Pro Activator yeast sachets are air-tight and aluminum-lined for consistent quality and storage for up to 3 years.

What are Bio-CO2 Pro Booster tablets made of?

Bio-CO2 Pro Booster tablets are made of dextrose sugar, which kickstarts the fermentation process.

What bubble count should I set when using a Fluval Bio-CO2 Pro system?

We recommend starting with the following bubble counts and making adjustments to suit your particular aquarium:
Bio-CO2 Pro 125: 12 bubbles / minute
Bio-CO2 Pro 250: 24 bubbles / minute
Bio-CO2 Pro 500: 48 bubbles / minute
The CO2 Indicator Set (Item #17561) conveniently mounts to the aquarium glass and monitors carbon dioxide levels in the water to help you in this process.

How long should a Bio-CO2 Pro system produce carbon dioxide for?

Bio-CO2 Pro systems produce carbon dioxide for up to 30 days.

My Bio-CO2 Pro system didn’t produce CO2 for as long as it should have. What happened?

It’s possible the bubble count was too high or an improper quantity of water or table sugar was used. The ambient room temperature also plays a role and can dramatically extend or shorten the CO2 production time.

Should I clean my Bio-CO2 Pro system before adding new Activator yeast sachets and Booster tablets?

Before adding new Activator yeast sachets and Booster tablets to your Bio-CO2 Pro system, empty the interior contents down a drain, thoroughly rinse out the reaction chamber and dry it using a soft cloth. We do not recommend the use of soaps or detergents.

Should I leave my Bio-CO2 Pro system running all the time?

Provided you do not exceed the recommended bubble count for your Bio-CO2 Pro system, there is no harm in leaving the unit running all the time. For optimized carbon dioxide uptake, turn on the system an hour before the lights come on and turn it off an hour before they shut off. The Bio-CO2 Pro 500 includes a solenoid valve to facilitate this process.

Can I add a solenoid valve to a Bio-CO2 Pro 125 or 250?

Yes! Solenoid valves can be added to Bio-CO2 Pro 125 and 250 systems.

What timers is the solenoid valve on the Bio-CO2 Pro 500 compatible with?

The solenoid valve on the Bio-CO2 Pro 500 is compatible with all mechanical and digital timers.

What is the CO2 airline tubing of Fluval Bio-CO2 Pro systems made from?

The CO2 airline tubing is made of polyurethane with a gas barrier.

Does the length of the CO2 airline tubing impact the efficiency of carbon dioxide injection into my aquarium?

Yes. We recommend measuring and cutting the CO2 airline tubing so that it follows a straight path from the bubble counter to the aquarium edge with no kinks or loops.

In which orientation should the inline check valve be installed?

The inline check valve should be installed with the black side facing away from the Bio-CO2 Pro system, towards the aquarium edge.

Where along the CO2 airline tubing should the inline check valve be installed?

The inline check valve should be installed about halfway between the bubble counter and the edge of the aquarium.

I am having difficulty opening the lid of my Bio-CO2 Pro system. What should I do?

Fully open the precision regulator to completely exhaust the CO2 supply and facilitate the opening of the reaction chamber lid. In the case of the Bio-CO2 Pro 500, the pressure release valve can be pressed to achieve the same results.

How does the pressure release valve on my Bio-CO2 Pro system work?

The pressure release valve automatically maintains the ideal pressure levels inside the reaction chamber in order to facilitate the fermentation process.

How do I know if I’m adding enough CO2 to my aquarium?

We recommend using a CO2 Indicator Set (Item #17561), which conveniently mounts to the aquarium glass and monitors carbon dioxide levels in the water.

Where should the nano bubble diffuser be positioned inside my aquarium?

The nano bubble diffuser should be positioned in the path of water flow within the bottom half of the aquarium, so the CO2 spends as long as possible in the water column to maximize plant uptake.

How frequently should I replace my Bio-CO2 Pro diffusers?

Routine replacement of CO2 diffusers is necessary every few months to maintain optimal carbon dioxide delivery.

My new ceramic CO2 diffuser disc is emitting large bubbles, rather than a fine mist. Is this normal?

Yes, new ceramic CO2 diffuser discs can take up to a week to begin emitting CO2 in a fine mist. It’s normal to see larger bubbles for the first few days of operation.

Can Bio-CO2 Pro systems be used in grow tents?

Bio-CO2 Pro systems are only intended for use in ornamental household aquariums.

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