The co2 algae circle

[zozo]

Hi all, Gas transfer does occur <"between different parts of the plant">, but what I think is more likely to happen is that the plant will begin to shed its submerged leaves, once it has become emersed with access to atmospheric CO2.

cheers Darrel

That might depend on the spieces..

Echinodorus is doing excactly what you say, it actualy completely stops making submersed leaves once some leaves are emersed. It sheds all submersed leaves and it only will make red colered leafstalks with a very smal red leaf on it. When this leaf emerses it grows bigger and all turns green. I have it over 2 years emersed now and it also never made runners submersed. Actualy no idea if Echinodorus does this in submersed form. But emersed form only makes new plantlets on the flower stalks.

But last summer i planted a large emersed form Dark red colored Lobelia Cardinalis in a 25cm deep water, after the summer it had grew a lot submersed form red/green new plantlets at the plantbase. Did cut the mother out and still have the rest submersed in the tank overwintering indoors under artificial light. All turned completely green and made quite a large carpet of Lobelias. So Lobelia definitively does vegetative propagation submersed from an emersed form mother.

 

[Danny]

Hmm interesting, some say better to have loved and lost then never loved at all but in this case would it be more beneficial to either never let the plant taste the atmosphere but if you did to always maintain the plant with some aerial growth so's never too take away the atmospheric co2 it has become accustomed to?

I get the impression never letting them break surface would be best, a bit like us coming up for a gulp of air then being forced to live under water knowing how much better it is above.

If by some way the plant can distinguish which it would rather live in then it would choose emersed and drop all submerged growth to focus on the preferred emersed I guess.

 

[Danny]

Going back to what Ceg said about the reaching, it does totally make sense now.

Looking at this stem I can see a difference of growth pattern within a couple of days from an increase in co2 and decrease in light intensity.

Less light but more co2 and the shoots are forming much closer together.

 

[ceg4048]

Based on this would it then be better to judge co2 efficiency by how dense stems grow and totally forget the theory they are leggy due to lack of light?

Yes. Poor gas exchange is the cause of legginess more info in the post https://www.ukaps.org/forum/threads/old-skool-returnee-london-tap-water.24040/#post-246834

I always assumed it was high lighting that kept them dense, could the same conclusion also be applied to carpeting plants?

Correct!

Cheers,

 

[Danny]

Yes. Poor gas exchange is the cause of legginess more info in the post https://www.ukaps.org/forum/threads/old-skool-returnee-london-tap-water.24040/#post-246834


Correct!

Cheers,

Your post linked there gives an excellent explanation!

One more light question.... if you have 20/30ppm co2 with excellent distribution are there really any actual "high" light plants?

HC Cuba for example, am I now right in thinking that because generally carpeting plants go hand in hand with high tech tanks it is more the fact of the co2 than the high light that allows it to grow effectively compared to a non co2 tank?

 

[Fiske]

HC Cuba for example, am I now right in thinking that because generally carpeting plants go hand in hand with high tech tanks it is more the fact of the co2 than the high light that allows it to grow effectively compared to a non co2 tank?

HC isn't particularily light hungry, it grows well in fairly low light too. It loves co2 though, and plenty of it.

 

[dw1305]

Hi all,

Lobelia Cardinalis in a 25cm deep water, after the summer it had grew a lot submersed form red/green new plantlets at the plantbase. Did cut the mother out and still have the rest submersed in the tank overwintering indoors under artificial light. All turned completely green and made quite a large carpet of Lobelias. So Lobelia definitively does vegetative propagation submersed from an emersed form mother.

I think plants from temperate regions are more likely to have annual cycles of growth, the same may apply to those from predictably regularly flooded areas. A lot of temperate plants form over-wintering leaf rosettes, like Lobelia cardinalis does, including some floating aquatic plants.

If you look at Lobelia cardinalis it <"is native to E.N. America right up into Canada">, where the marshes and lakes are going to be frozen for months at a time.

It is a humming-bird pollinated flower, so it looks exotic, but <"Ruby-throated Hummingbirds occur right up into Canada"> in the summer, when the plant is emersed and flowering.

cheers Darrel

 

[ceg4048]

One more light question.... if you have 20/30ppm co2 with excellent distribution are there really any actual "high" light plants?

No, this is all an illusion created by those wishing to sell light bulbs. These same folks will tell you to change you bulbs every "X" number of months.
Light beyond the minimum amount acts as a metabolic accelerator. If you wish to increase the growth rate then certainly you can use more light, but this causes an increase in the demand for CO2. Scapers wishing to increase their plant mass quickly will throw lots of light at their plants to get them to bulk up quickly.. So when you see the expression "...requires high light..." used to describe a plant you need to fill in the blanks, i.e "Requires high light to grow faster so you can show off your amazing aquascape to the judges". Strong lighting also stresses the plants which triggers them to produce pigments to protect themselves from sunburn. These protective pigments appeal to our aesthetic sense, so this is another reason a specific plant "...requires high light..." to produce exotic colors.

HC Cuba for example, am I now right in thinking that because generally carpeting plants go hand in hand with high tech tanks it is more the fact of the co2 than the high light that allows it to grow effectively compared to a non co2 tank?

That's correct. There are certainly Low Light plants, such as ferns, moss, anubias and so forth, but there are no such things as High Light plants, only High CO2 plants.
There are many plants such as HC which are more often than, not found in their natural habitat only semi-submerged, so they are not used to being thrown deep under water, so they are not efficient at using aqueous CO2. Others live in waters heavily stained with tannis which filter out quite a bit of the light.

Of course, you can use high light, but it's like fire. Use it to prepare a meal but avoid being burned....

Cheers,

 

[Danny]

No, this is all an illusion created by those wishing to sell light bulbs. These same folks will tell you to change you bulbs every "X" number of months.
Light beyond the minimum amount acts as a metabolic accelerator. If you wish to increase the growth rate then certainly you can use more light, but this causes an increase in the demand for CO2. Scapers wishing to increase their plant mass quickly will throw lots of light at their plants to get them to bulk up quickly.. So when you see the expression "...requires high light..." used to describe a plant you need to fill in the blanks, i.e "Requires high light to grow faster so you can show off your amazing aquascape to the judges". Strong lighting also stresses the plants which triggers them to produce pigments to protect themselves from sunburn. These protective pigments appeal to our aesthetic sense, so this is another reason a specific plant "...requires high light..." to produce exotic colors.


That's correct. There are certainly Low Light plants, such as ferns, moss, anubias and so forth, but there are no such things as High Light plants, only High CO2 plants.
There are many plants such as HC which are more often than, not found in their natural habitat only semi-submerged, so they are not used to being thrown deep under water, so they are not efficient at using aqueous CO2. Others live in waters heavily stained with tannis which filter out quite a bit of the light.

Of course, you can use high light, but it's like fire. Use it to prepare a meal but avoid being burned....

Cheers,

Thanks Ceg you have certainly cleared everything up for me and hopefully I'll be able to put everything into practice now.