Ole's refute to allelopathy having any significant effect on algae in aquariums

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,696
745
113
MarmoteX;33745 said:
A limiting factor is not only the one that is on a low concentration, but can be the one in a high concentration.

Competition between algae and plants is not exactly the type of competition there is between species on the same niche. So I guess there wouldn`t be a total "displacement" of algae. For example potassium is an inhibitor in some algae reproduction (i don´t remember where i read it).

Mr Barr have you done experiments on algae and high concentrations of nutrients?. Like the one you did for plants for the EI. It would be interesting to see how concentration gradient of any nutrient plays roll on algae development.

You are referring to Shelford's law of tolerances, which addresses the upper inhibiting ranges as well as limiting ranges(unlike Liebig's law)?

No, not really, but I have not seen much evidence other than for BGA with respect to NO3, PO4 for Green spot, but neither of these are single variables.

Good CO2, organic matter, no BGA to start with etc are all dependent co-variables with thos, so no, I've not done it pre se, however, I've also never seen any evidence that the situation you mention exists either;)

I need observations 1st, and then ........can make hypothesis to test.
In algal cultures without plants, that is another question and situation.
But.........if you remove plants, it's not really applied to aquatic plants:cool:

You have to be careful applying one reference broadly to algae, like the K+ inhibitor, and b specific to the species that cause us issues, that narrows things down to 10-12 species pretty much and they are all FW warmer water species etc.

Regards,
Tom Barr
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
Threads like this are why I spend so much time lurking this forum. I enjoy seeing a bad idea refuted, even if I'm 2-3 years late getting to the thread. Theories always seem to abound in the hobby, but testing those ideas often seems on the short side. I find my self even thinking, "I'll get around to testing that concept" and never do. Honest critique seems to be met as a personal attack quite often as well. I enjoy the fact that it's encouraged here.

-Philosophos
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,696
745
113
the personal attack? hahahaa

Yes, testing and the results, that's what science is all about.
You have plenty of academics that postulate and speculate, we do that all the time.............but when we find something that might be fruitful, or low hanging fruit and is something we can test, then we go after it, the high risk hypohtesis better have some good foundation and pay off otherwise.


But hobbyist rarely test to answer a specific question like this.
Few know diddly about algae and it's life history, that is painfully clear.
I do not fault them for this however.
Most overlook this stuff. I'm just unwilling to to do so.

It does not make me a bunch of pals...........but my goal is getting at the truth about what is happening in planted tanks with algae, nutrients, growth etc, not being your pal really. A real friend will be honest with you about something and not take it personally.

I don't want those other folks as my fiends.

I do not think DW's idea to discuss that topic was "bad", it was speculation and we can do a few things to see about it and then test and observe. This way we know more about it and it appears to be minor/if significant at all.

These are just questions that need to be asked and addressed, whether or not they are bad, false etc, is just a matter of the process really. Little gets resolved without testing and seeing if you can confirm or deny etc.

Regards,
Tom Barr
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
I agree with your sentiment; I'd rather be told I'm wrong than have my ego stroked while riding off a cliff. At the same time, it's funny how many people would agree to that idea in concept but behave in the opposite way in practice. The way humanity as a whole clings to reasoning that frequently falls under the category of logical fallacy is kind of surprising. It makes me want to study social psychology and the neurology behind it.

I don't think exploring the idea was bad either. I think the error was to publish for the general public what a number of people saw as conjecture. The concept tied everything else together in much the same method as a certain teacup orbiting the earth that will remain nameless. Even if the concept had turned out to be sound, I don't believe the method of coming to the conclusion was.

On a side note, I've got a question (of course a question was coming). for a wet start with freshly planted tank, should the target nutrient levels be altered from the ranges you've previously stated for established growth? My brain is crapping out today, and I can't find much on the subject. Dry start is out of the question for this round because of fauna juggling.

-Philosophos
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,696
745
113
Philosophos;34988 said:
I agree with your sentiment; I'd rather be told I'm wrong than have my ego stroked while riding off a cliff. At the same time, it's funny how many people would agree to that idea in concept but behave in the opposite way in practice. The way humanity as a whole clings to reasoning that frequently falls under the category of logical fallacy is kind of surprising. It makes me want to study social psychology and the neurology behind it.

Generally wants me to run and get stick and start beating the fallacy to death:p
I do it here and there, but I admit to it when I do. When you do not fess and are no longer honest, I really cannot trust that person to make sane decisions.

Problem is, then some cult or coot runs around trying to get more of their faithful to their flock. I remember Jim Jones a bit too much I guess.

I don't think exploring the idea was bad either. I think the error was to publish for the general public what a number of people saw as conjecture. The concept tied everything else together in much the same method as a certain teacup orbiting the earth that will remain nameless. Even if the concept had turned out to be sound, I don't believe the method of coming to the conclusion was.

Yes. You have a point against the defense of putting allelopathy in the book.
I think they where clear is was conjecture, problem is..........the public is wonderful at taking conjecture, and making it fact.

On a side note, I've got a question (of course a question was coming). for a wet start with freshly planted tank, should the target nutrient levels be altered from the ranges you've previously stated for established growth? My brain is crapping out today, and I can't find much on the subject. Dry start is out of the question for this round because of fauna juggling.

-Philosophos

It will not hurt to have the same levels of PPM's etc, but........the plants will not reuire/demand as much generally, mostly since there's less biomass and root establishment. Which is a common sense thing, but that does not lead to algae etc any more than anything else.

What is key, good CO2, lower/moderate lighting, as much plant biomass as you can, do frequent water changes on any new tank(2-3x a week for 2 weeks, then 2x a week fir the next 1-2 months till things grow in well).

Regards,
Tom Barr
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
Rationality, for some, is one incredible endorphin rush. I think quite often it leads to being branded as a troll. I could see you getting banned from some of the fluffier fish sites for having an opinion. This is assuming you changed your ID and proxied.

Jim Jones is a good example. I'll leave it at that before I start leaving links to pharyngula laying around.

As for the book, maybe it is the people more than the author. Still, why not test the idea and publish a better book? I think it's the pain of every person that is ahead of their time, heads in their field or just generally knowledgeable that those first learning from them will interpret their ideas as fact. Worse yet, they try to make their previous perceptions right at the same time as the contradictory evidence. The reactions of those being followed, in turn, is a pretty good occasion for a bowl of popcorn. Sometimes you'll get a free glass kool-aid out of the deal, even if it does smell like almonds.

Anyhow, thanks for the advice on fert concentrations. It seemed like the rational conclusion, but it is rather counter-intuitive from how I've previously thought of things. What's with the frequent water changes at first? I'm trying to add it up in my head a few different ways but nothing is coming out. The best I can come up with is possible nutrient deficiencies, or a safer way to establish the algorithm of EI without starting at a mass dose.

-Philosophos

*edit* Ok, figured out that it was probably to establish a cycle. I'll play with things and see what happens.
 

wilsar

Prolific Poster
Jan 10, 2009
39
0
6
i believe there is "something" to different species affecting others (even if insignificant for our hobby), if we look at trees, each species have different nutrient ratio needs and also different visitors. aquatic plants also specialize in different nutrient uptake ratios and also host different bacterial/fungal visitors or residents. i believe it is within this scope that causes some species to "repel" or "stimulate" others growth and well being. if the system favours one species over another, ie.being slightly more acidic loving plant, then it would affect the non favored species negatively. one could argue that this is due to the non favored species liking a less acidic enviroment than given but i believe it is due to a lower life strata that has an influence more than we know at present. we do know aquatic plants can adjust and grow in a wide range of conditions, but each species has a particular preference in which it thrives.
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
I agree. Everything effects everything to some extent. Some plants grow faster than others; this is why I trim some plants more than others. This is simple resource competition. Some plants overshadow others because of their faster growth, this makes a clear cut case of eliminating photosynthesis. Even allelopathy is known to occur.

The concept that submerged aquatic macrophytes within an aquarium are constantly killing each other off because of the secondary metabolites they put off, without showing conclusive evidence for it, is an untested theory. It's even worse to attribute unexplained issues with plants to it, without showing why. I don't blame cancerous stem cells every time I'm not sure what's wrong with my health.

-Philosophos
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,696
745
113
So how might you go about demonstrating Allelopathy in an aquarium?

1. What would serve as a control system for reference?
2. What would serve as a known upper bound for allelopathic effects in situ?
3. Which species would you chose to do this with and why?

If these cannot be done, thought out and through all the way, then there's little hope of answering the basics.

I think it's an issue of common sense and likelihood really.
How likely is this effect? How strong/intense is it? If it's likely and has a strong effect, then we should be able to easily demonstrate it correct?

Our observations do not lend well to the common sense that it's a "significant factor" in controlling algae, nor between species of aquatic plants.

I find it curious that most of the pro allelopathy folks(well, 100% so all at this point in time I've talked with) have never done a single allelopathic experiment or even read any background on how to do a basic field test for it.

In vitro test wells are hardly a field test. The concentrations are extreme, they are not representative of the living plant in a natural or aquarium setting.
Diana Walstad used extensive tables and the fact there are cell extracts that kill algae for support.

This is NOT support for this effect occurring in situ/in a living plant/field test.
Many cell contents have toxic/inhibitory chemicals if you grind them up, but give off none of these under live conditions.

Regards,
Tom Barr
 

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
1
36
Surprise, AZ
Rather Than Linking

Hi,

I was wondering if it would be possible to get permission to get Ole's refute to allelopathy and post it here. :)

It is about the best explanation I have seen. Not to mention a recurring theme. :cool:

Biollante
 

Philosophos

Lifetime Charter Member
Lifetime Member
Mar 12, 2009
1,346
0
36
The entirety of Tropica's articles are pretty cool. A lot of it is what you've heard already, but there's some extra bits. I think the all time best bit on that site is their video of hunting for P. helferi; they show a giant mound of the stuff in its natural habitat.

Now what's got me with this thread is seeing Professor Meyers on page 1 back in '06. Would that be the PZ Meyers of scienceblogs.com/Pharyngula infamy? If so... wow :D
 
Last edited by a moderator: