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Plants that use bicarbonates for photosynthesis

1416 Views 3 Replies 3 Participants Last post by  boringname
Some plants can thrive in low CO2 conditions by getting the carbon needed for photosynthesis from bicarbonates in the water. Sounds like an easy way to avoid excel or CO2 systems. But I've only found three aquarium plants described as being able to do this:


Does anyone know of other aquarium plant species with this ability? Preferably pretty ones.
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Hydrilla uses indirect bicarb and Egeria is similar.
Pondweeds do, Stuckenia and Potamogeton etc.
Maberley(1983) and Madsen have decent papers of the topic.
Milfoils do also.

The bicarb is used only when a threshold of lower CO2 in no longer available or a good trade offs, then the plant switches to HCO3 use.

So.......if you want to increase growth, simply add CO2 gas, in nature, the plants have to make do and get whatever is available to gain an advantage vs another aquatic weed. So C4 metabolism and CAM well as bicarbonate use when the CO2 gets low are all viable advantages. A small change in acquiring carbon over time can translate into huge gains in biomass over a year or more.

You might read pages 6-9 or so.

Tom Barr
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Thanks for the link Tom it was very interesting. It seems that the as long as a plant can survive at a ph higher than 8.2 the use of bicarbonates can be taken for granted. Now I will look for a plant like that whose appearance goes beyond the long-wavy-green theme.
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