Why is carbon dioxide (CO2) the most important plant nutrient in the aquarium?

Carbon dioxide is the nutritional basis for aquatic plants which is supplemented through micro and macronutrients and light. The balance between all these elements is necessary for thriving plant growth in the aquarium. In photosynthesis light energy binds CO2 with the water and sugar is produced (nutrition for the plant). During this process oxygen (O2), which is required by other living organisms (bacteria, all animals), is released.

In the air the carbon dioxide content is currently constant at about 400 ppm (parts per million parts). Therefore it is always available in sufficient and – more importantly - in constant amounts for the land plants.

Under water this is totally different. Due to the partial pressure gradient to the atmosphere the carbon dioxide content in the water adjusts to about 2-4 mg/l when there is no additional carbon dioxide supply. This is not enough for the underwater plants to grow well.

This effect can frequently be observed in the wild. Tropical aquatic plants often form densely concentrated “colonies” at spots where water containing carbon dioxide seeps. As soon as the carbon dioxide in the water becomes too low, the aquatic plants withdraw from the waters again.

In aquariums without any additional carbon dioxide supply, there is always a lack of this important plant nutrient, since the recommended value for good plant growth lies between about 15 and 25 (up to 35) ml/g. This can only be compensated by supplying carbon dioxide gas with a CO2 system. For this purpose the PROFLORA CO2 plant care systems in the versions PROFLORA Bio CO2 or as pressurised gas cylinders variants Disposable (u) and Refillable (m) are very well suited.

As to the perfectly reasonable objections of some aquarium owners: “My plants display flourishing growth even without additional CO2 fertilisation.”

This may well be true, but you need to know the exact circumstances of the aquarium in case. In aquariums with relatively weak light conditions and with plants which tend to be slower growing, such as various Anubias, fern and Cryptocoryne species, the amount of CO2 produced by fish and bacteria, can definitely be sufficient for the survival and growth of the plants. But these cannot be described as having vigorous growth if you compare them with plants with an additional carbon dioxide supply.

Conclusion

Carbon dioxide (CO2) is the most important plant nutrient for aquatic plants in our aquariums. Yet the importance of additional CO2 dosing is underestimated by some aquarium owners. To counteract this lack carbon dioxide, which can be added through pressurised gas cylinders or bio-CO2, is required. Liquid CO2, as we will explain in a five-part blog, Is not available under normal conditions (temperature: 20 °C and atmospheric pressure: 1 bar or 1013 hPa).

© 18.06.2016
Matthias Wiesensee
Matthias Wiesensee
M.Sc. Wirtschaftsinformatik

Social Media, Online Marketing, Homepage, Kundenservice, Problemlöser, Fotografie, Blogger, Tauchen, Inlineskating, Aquaristik, Gartenteich, Reisen, Technik, Elektronische Musik

About me: Seit Teenagerzeiten mit Aquarien in Kontakt. Klassische Fischaquarien, reine Pflanzenaquarien bis hin zum Aquascape. Aber auch ein Gartenteich und Riffaquarien begleiten mich privat im Hobby. Als Wirtschaftsinformatiker, M.Sc. bin ich als Online Marketing Manager bei JBL für die Bereiche Social Media, Webentwicklung und der Kommunikation mit dem Anwender der JBL Produkte zuständig und kenne die JBL Produkte im Detail.

Comments

A word about cookies before we continue

The JBL Homepage also uses several types of cookies to provide you with full functionality and many services: We require technical and functional cookies to ensure that everything works when you visit this website. We also use cookies for marketing purposes. This ensures that we recognise you when you visit our extensive site again, that we can measure the success of our campaigns and that the personalisation cookies allow us to address you individually and directly, adapted to your needs - even outside our website. You can determine at any time - even at a later date - which cookies you allow and which you do not allow (more on this under "Change settings").

The JBL website uses several types of cookies to provide you with full functionality and many services: Technical and functional cookies are absolutely necessary so that everything works when you visit this website. In addition, we use cookies for marketing purposes. You can determine at any time - even at a later date - which cookies you allow and which you do not (more on this under "Change settings").

Our data protection declaration tells you how we process personal data and what purposes we use the data processing for. tells you how we process personal data and what purposes we use the data processing for. Please confirm the use of all cookies by clicking "Accept" - and you're on your way.

Are you over 16 years old? Then confirm the use of all cookies with "Noticed" and you are ready to go.

Choose your cookie settings

Technical and functional cookies, so that everything works when you visit our website.
Marketing cookies, so that we recognize you on our pages and can measure the success of our campaigns.
I accept the YouTube Terms of Service and confirm that I have read and understood the YouTube Terms of Service .

PUSH messages from JBL

What are PUSH messages? As part of the W3C standard, web notifications define an API for end-user notifications that are sent to the user's desktop and/or mobile devices via the browser. Notifications appear on the end devices as they are familiar to the end user from apps installed on the device (e.g. emails). Notifications appear on the end user’s device, just like an app (e.g. for emails) installed on the device.

These notifications enable a website operator to contact its users whenever they have a browser open - it doesn’t matter whether the user is currently visiting the website or not.

To be able to send web push notifications, all you need is a website with a web push code installed. This allows brands without apps to take advantage of many of the benefits of push notifications (personalised real-time communications at just the right moment).

Web notifications are part of the W3C standard and define an API for end user notifications. A notification makes it possible to inform the user about an event, such as a new blog post, outside the context of a website.

JBL GmbH & Co. KG provides this service free of charge, and it is easy to activate or deactivate.