I've read (on SeaChem's website) that tanks dosed with both injected CO2 gas and liquid sources of Carbon (eg Excel or EasyCarbo) are better for plants than those with only injected CO2 (is this true?). I understand that the liquid Carbon products contain traces of biocides (is this merely to act as a preservative for the product?). And this has me wondering: is there a difference in how algae can compete with vascular plants for liquid carbon versus dissolved CO2? That is, all things being equal, is liquid Carbon more or less advantageous to algae competing against vascular plants than injected CO2 gas?
Algae: Liquid versus injected CO2 preference
- Thread starter micmath
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So I probably wasn't totally clear what my question was but I was specifically asking about the relative benefits of liquid Carbon products versus injected CO2 on plants firstly. I've heard people say that if CO2 were a 10 then liquid Carbon would be about a 6 in terms of usefulness to plant growth. So, according to that, CO2 is almost twice as beneficial to vascular plants as liquid Carbon. I don't know what that ratio is based on, but I'd be curious if you agree with that ratio of 10 to 6.
Secondly, I'm curios if that ratio of benefit remains the same if we switch to talking about algae. So, for example, if a vascular plant can only derive 60% benefit from liquid Carbon, versus dissolved CO2, would algae also be deprived of that exact same 40%? Or are algae a little better at adjusting to liquid Carbon, so that they might only be deprived of say 10%.
If this were true, then all other things being equal, it would benefit algae (by depriving them less than their competition ) to switch from injected CO2 to liquid Carbon.
Sounds like a strange thing to ask, I know. But that, sadly, is the kind of question my brain thinks up.
Secondly, I'm curios if that ratio of benefit remains the same if we switch to talking about algae. So, for example, if a vascular plant can only derive 60% benefit from liquid Carbon, versus dissolved CO2, would algae also be deprived of that exact same 40%? Or are algae a little better at adjusting to liquid Carbon, so that they might only be deprived of say 10%.
If this were true, then all other things being equal, it would benefit algae (by depriving them less than their competition ) to switch from injected CO2 to liquid Carbon.
Sounds like a strange thing to ask, I know. But that, sadly, is the kind of question my brain thinks up.
It isn´t really "liquid Co2". EC/Excel contain Glutaraldehyd and this is something similar stuff like yours dentalist uses for cleaning his instruments and so on. In a tank Gluteral will be destroyed by bakterias or whatever so and this activity produces some chemical reactions and also Co2, but this will be only a little bit.
At last there are only few plants that may take some advantage from dosing EC like some Cryptocoryne and a few similar slow pace stuff.
For most plants dosing EC will only have little and/or really none effect in a well working tank with pressured Co2.
You may also keep in mind that there are some (sensitive) plants, moos and so on, who don´t tolarete really that good EC in the long run.
So, I wouldn´t use EC in any tank as "permanent addOn fertilizer"; work on yours tank, fert dosing + Co2 and grow will be for sure fine (without EC). Grow rate will be mostly be limited in many tank by the light, so if you want more grow = add just more light. (certainly doing so may make some things more difficult)
EC is "ok" for fighting Red algaes (BBA, Staghorn) like H202 is "ok" for fighting Green (Hair)/BGA.
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I would say if CO2 correctly used is 10, then Excel etc, is about 2-maybe a 3.
Some are okay with this for many aquariums. Particularly nano aquariums where slow grow growth is preferable.
Or if you are prone to neglecting your tank and trimming.
Algae are not deprived of resources in aquariums, even in tanks where no ferts are added and aquarist attempt to minimize all nutrients etc, they still have many issues if they add a fair amount of light.
Algae are never CO2 limited, aquatic plants are very often, so they stop growing and simply become substrate for algae to attach to and grow on.
If you want nice plants= focus on their growth, not worrying/trying to outwit algae.
Some are okay with this for many aquariums. Particularly nano aquariums where slow grow growth is preferable.
Or if you are prone to neglecting your tank and trimming.
Algae are not deprived of resources in aquariums, even in tanks where no ferts are added and aquarist attempt to minimize all nutrients etc, they still have many issues if they add a fair amount of light.
Algae are never CO2 limited, aquatic plants are very often, so they stop growing and simply become substrate for algae to attach to and grow on.
If you want nice plants= focus on their growth, not worrying/trying to outwit algae.
Well, I didn't ask this question because I was worried. I'm curious -- a bit of a science geek I saw claims on the Seachem website saying their liquid CO2 source was 60% [1] as effective as injected CO2 gas. i don't know what that is based on, they don't provide any details. Tom says it's more like 20 or 30%. I find that very interesting.
As for algae, from what I've heard, if you have an environment that can support the growth of plants, that environment will also support the growth of algae event better, surely? People say that algae can grow with less light, less CO2 and less nutrients available than plants can. So why isn't every body of water and aquarium with plants also covered with algae? (Obviously rooted plants have an advantage when all the nutrients are below the river/pond bed.) But Tom's reference to plants becoming a "substrate" for algae, and the key to avoiding that is to keep plants healthy, is a bit of a revelation in my opinion and possibly answers this mystery. Do healthy plants have a way to suppress algae growing on their surfaces (and conversely unhealthy plants don't)?
[1] "If CO2 is a 10, Excel is a 6-7." http://www.seachem.com/support/FAQs/FlourishExcel.html
I saw claims on the Seachem website saying their liquid CO2 source was 60% [1] as effective as injected CO2 gas. i don't know what that is based on, they don't provide any details. Tom says it's more like 20 or 30%. I find that very interesting.As for algae, from what I've heard, if you have an environment that can support the growth of plants, that environment will also support the growth of algae event better, surely? People say that algae can grow with less light, less CO2 and less nutrients available than plants can. So why isn't every body of water and aquarium with plants also covered with algae? (Obviously rooted plants have an advantage when all the nutrients are below the river/pond bed.) But Tom's reference to plants becoming a "substrate" for algae, and the key to avoiding that is to keep plants healthy, is a bit of a revelation in my opinion and possibly answers this mystery. Do healthy plants have a way to suppress algae growing on their surfaces (and conversely unhealthy plants don't)?
[1] "If CO2 is a 10, Excel is a 6-7." http://www.seachem.com/support/FAQs/FlourishExcel.html
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they get about 200-300% more growth usign Excel vs a control.
Compared to cO2, then the growth is 10X faster.
But Excel tends to be easier to use for many people if they add it daily.
So the plants tend to stay cleaner........and less algae.
and they grow slower...........all things many aquarist seek.
the quesion you are now askign is a different question: why do plants grow and not algae in this system ?
Well, why do Trees grows and not herbaceous weeds? What happens if you cut the trees down? You'll get weeds.
Similar thing with algae and aquatic plants.
They both use the same similar resources, but at very different scales and time trajectories.
Once established, plants define the system, not the nutrients.
About the only real competition interaction is for light between these two groups.
We add lots of plants, so we create a forest rather fast and then algae really does not have much chance, we also exposure algae to air with water changes, and add herbivores that eat algae, prune old parts of plants out of the tank, enrich with CO2 to speed the growth rate of the plants up 10X, so it takes a much shorter time. algae does not have as much time to colonize plant leaves.
The initial goal is have a nice healthy planted tank, so focus on the needs for the plants, the algae are indirect consequences of poor aquatic plant care. If you want nice planted tanks, then focus on plants.
Pretty simple. I have not changed this idea since 1993 or so.
Compared to cO2, then the growth is 10X faster.
But Excel tends to be easier to use for many people if they add it daily.
So the plants tend to stay cleaner........and less algae.
and they grow slower...........all things many aquarist seek.
the quesion you are now askign is a different question: why do plants grow and not algae in this system ?
Well, why do Trees grows and not herbaceous weeds? What happens if you cut the trees down? You'll get weeds.
Similar thing with algae and aquatic plants.
They both use the same similar resources, but at very different scales and time trajectories.
Once established, plants define the system, not the nutrients.
About the only real competition interaction is for light between these two groups.
We add lots of plants, so we create a forest rather fast and then algae really does not have much chance, we also exposure algae to air with water changes, and add herbivores that eat algae, prune old parts of plants out of the tank, enrich with CO2 to speed the growth rate of the plants up 10X, so it takes a much shorter time. algae does not have as much time to colonize plant leaves.
The initial goal is have a nice healthy planted tank, so focus on the needs for the plants, the algae are indirect consequences of poor aquatic plant care. If you want nice planted tanks, then focus on plants.
Pretty simple. I have not changed this idea since 1993 or so.
Yes, I know my mind wanders, but I'm generally asking about how plants versus algae gain advantage in an environment (frankly I think I have a lot of respect for algae, all things considered), it was just the Excel claim that got me wondering if that same benefit applied to algae as to plants.
And "why do Trees grows and not herbaceous weeds?" is an absolutely brilliant analogy!! Thanks everyone for all this insight.
And "why do Trees grows and not herbaceous weeds?" is an absolutely brilliant analogy!! Thanks everyone for all this insight.
Abusing freedom of speech
Warning, amateur speculation here:
In a forest there's not enough light at ground level for weeds to grow as well as in the plains.
I don't think the same is true of algae vs vascular plants. If limited light was the only issue, algae would grow just fine on the tops of plants. Most weeds can't grow on trees but most algae can grow on plants. There has to be something else, maybe in addition to the light issue.
Allelopathy it isn't, or else tanks filtered with activated carbon would fill with algae (I learned this from Tom).
As we know, the best deterrent for algae is a leaf that grows.
What if something happens at the very contact of algae with plant leaves? Maybe something that the growing tissue does locally, like physically kicking algae spores, or eating them, or depleting something locally etc. Or maybe algae themselves dislike the local dynamic of the growing leaf, with all those cells appearing and shifting around. Maybe they simply like only immovable surfaces as substrate and they can't attach to something that "wiggles".
Tom, 10 years from now, when you get the Nobel prize for this discovery, please invite me to Stockholm for the ceremony
Warning, amateur speculation here:
In a forest there's not enough light at ground level for weeds to grow as well as in the plains.
I don't think the same is true of algae vs vascular plants. If limited light was the only issue, algae would grow just fine on the tops of plants. Most weeds can't grow on trees but most algae can grow on plants. There has to be something else, maybe in addition to the light issue.
Allelopathy it isn't, or else tanks filtered with activated carbon would fill with algae (I learned this from Tom).
As we know, the best deterrent for algae is a leaf that grows.
What if something happens at the very contact of algae with plant leaves? Maybe something that the growing tissue does locally, like physically kicking algae spores, or eating them, or depleting something locally etc. Or maybe algae themselves dislike the local dynamic of the growing leaf, with all those cells appearing and shifting around. Maybe they simply like only immovable surfaces as substrate and they can't attach to something that "wiggles".
Tom, 10 years from now, when you get the Nobel prize for this discovery, please invite me to Stockholm for the ceremony
Ah, "allelopathy," that is the word I was looking for! I've read that some plants like hornwort at least do actively suppress algae, though I have not seen any irrefutable evidence of this claim.
Coincidentally, I was reading something about this whole subject just last night. It's from a book by Berti Gesting, and regarding the competition between vascular plants and algae, and the influence of resources in the environment he writes [emphasis mine]:
"In aquaria with healthy and thriving plants the algae will not find the necessary essentials to live. After all, excessive algae only indicate a breakdown of the biological balance in the aquarium. Algae prefer an oxidising environment, aquarium plants, on the other hand, a reducing environment. Therefore, if the aquarium is set up and maintained in accordance with the biological laws of nature, algae cannot become a problem."
I'm not clear what part of the environment the author is referring to, the oxidization of ammonium possibly? Or Iron? There is a good deal of chemistry leading up to that chapter which I need to reread If so then the difference would explained by things like pH, GH, CO2, water flow... in short all the stuff that aquarists work to get right all the time.
Coincidentally, I was reading something about this whole subject just last night. It's from a book by Berti Gesting, and regarding the competition between vascular plants and algae, and the influence of resources in the environment he writes [emphasis mine]:
"In aquaria with healthy and thriving plants the algae will not find the necessary essentials to live. After all, excessive algae only indicate a breakdown of the biological balance in the aquarium. Algae prefer an oxidising environment, aquarium plants, on the other hand, a reducing environment. Therefore, if the aquarium is set up and maintained in accordance with the biological laws of nature, algae cannot become a problem."
I'm not clear what part of the environment the author is referring to, the oxidization of ammonium possibly? Or Iron? There is a good deal of chemistry leading up to that chapter which I need to reread
If so then the difference would explained by things like pH, GH, CO2, water flow... in short all the stuff that aquarists work to get right all the time.