Nutrients cause algae ; forum fights

ibanezfrelon

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I think a lot of you guys here on Barrreport had these situations , when you are caught in discutions with certain people on your local forums that still belive that nutrients cause algae..
PO4 is on the top of the list here folloved by NO3 , Fe etc.
Fertilizing a newly started tank gets in a crossfire quite often..
Whenever someone comes with some algae problem you can hear a whole bunch of ''advices'' like ; stop fertilizing , use phosphate remover , nitrate remover , algacide , increase the lights etc.
Very few times you hear stuff like; increase co2 , lower the lights...
Never any hard evidence behind those ''advices''.
Some more experienced aquarists give their ''years spent in the hoby'' as evidence..

It's actualy pretty disturbing to get into such arguments , specially when there's ''nutrients cause algae'' atmosphere.
I saw a lot of spicy discussions on the subject from Tom Barr and am amazed the way he handles the attacks from ''non belivers'' out there.
On the other hand he (Tom) is filled with experience , knowledge and a whole bunch of scientific tests behind him that prove his statements.
For me and others what's left as an argument is experience with 1 or 2 tank and presenting Barr's scientific tests that prove this and that.

I have a 30 lit tank with 1x14w t8 that i use to put the extra plants that's left after trimming , i also use it as a quarantine tank when i get some new fish.
Don't have co2 system for it but i dose EC (Excell) , no algae issues.
I was thinking of using that tank to make some tests that would prove that those notorious nutrients don't cause algae , i would document the tests etc..
..but i could use some guidelines for those tests..

..ya know, how long should a test last , what dosages of ferts to use and so on..
 

dutchy

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I recognize that. I have that all the time on Dutch forums. I keep showing them my pics and ask them if their statement that high PO4 causes algae is right then why don't I have it. Beginners are easy, but it's the more experienced aquarists that make the trouble. They don't make the effort to help the topicstarter but attack me on my advice. Sometimes I get them in such a thight spot that they start to get personal on me. That's easy, I report the post, it gets deleted and they get a warning.

It's a hard fight, but I can notice I'm getting somewhere. People taking the advice and reporting back telling everyone the succes they are having. Those are the best.

Sometimes I don't give any advice. I just let it go wrong. You might ask yourself why, but it makes sense. After some weeks, months, the topicstarter comes back and says the advice (s)he got it didn't help at all. Then I give my advice. The ones that were the first to give a wrong advice will keep their mouth shut. If not, I remind them of their wrong advice. Both parties learned something :)

A lot of advice is based on assumptions and myths, it always works to ask them to back it up with scientific research papers. I have a lot of scientific documentation to fall back to.

I could tell a lot of nice anecdotes about discussions I had, but I would type pages and pages. It takes months to notice some difference in way of thinking. Some are easy to convince, you will never convince some others. Best is when someone you helped posts a pic of an algae infested slimy Echino with one big 8 inch leaf sticking out since (s)he started to use EI.

The only downside to it that a lot of people just ask questions, without doing a search first. That way you keep typing the same over and over again. I solved that using cut and paste from some documents I have with standard answers. :)

If you read a lot of Toms discussions you can learn from that too. Make clear their hypothesis can be falsified, and explain them why. Tough guy that can beat that.

Good luck on your quest ;)

regards,
dutchy
 
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Frank Lawler

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Perhaps some of the suspicion is due to the fact that the exact mechanism by which a nutrient-filled tank can supress algae has never been explained. The standard reply that plants thereby outcompete algae seems somewhat incomplete.
 

nipat

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I think it's partly because most people still rely on root tabs as main fert.
That is the nutrient they know. Disturbing that ‘nutrient’ to water column
can cause algae.
 
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ibanezfrelon

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I kind of think that EGO is one of the biggest problems here. Ego makes people defend their original statement without proper arguments , and as Dutchy said , that often leads to personal insults etc.
I think it's important to accept some fundamental truths in this hoby , things like ; nutrients don't cause algae in planted aquariums etc.
..this way people could focus more on getting a nice plant growth and put more focus on things like light , co2 , flow , tank hygiene and so on..

Frank , as far as i'm concerned , nutrients don't have to supress algae , all i ask from them is to feed my plants and to not CAUSE algae , those are good enough reasons to keep dosing , even without scientific evidence to how plants outcompetes the algae. ( although i would say that taking away the light with plant biomas is the main competition here and not taking all the nutrients)
 

Tom Barr

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I was pondering this issue a couple of days ago with respect to Justus Liebig, long dead German guy.

So what do we have?
Two different general groups: submersed plants and algae.

If we know adding x amount of ferts(whatever one you want to pick or chose), to the 90% 100% maximum yield range, adding more simply will not result in more growth.
You have to do something else to increase the yield.

However, this is also true for algae, not just plants.

Micro_Growth_Curve_Use.jpg


So adding anything beyond the C range is not going to increase algae growth, it cannot and Liebig's law predicts this for all plants/algae/autotrophs.
So why would it matter if the 90-100% max yield concentration for Caldophora is 0.01ppm for CO2 and 0.001 for PO4, 0.01ppm for NO3?

Can we limit algae and also provide max growth for plants?
No, clearly not.

So what happens when folks stop adding ferts or add very little and they see improvements?
Well, again...........Liebig's Law also predicts a shift from say poor CO2 limitation(eg, they have high nutrients and also algae), and then say PO4 becomes more limiting.
This change from one limiting nutrient to another in terms of PLANTS, not anything to do with algae demands..............explains why this observation is true, but also why for many, that adding high nutrients in conjunction with good CO2........also has good results as well.
The naysayers do not have independent CO2.

CO2 is tricky, and many assume it is not, that is a huge problem.
Light is yet another tricky issue, but the solution is much eaiser than the CO2.

Still, if you stick with Liebig's law, which Paul and Kevin did with PMDD years ago.........it's fairly good at predicting the outcomes.
All you need to know is the compensation points for algae and plants and that C ranges.

Given the much lower points for algae, the upper toxic ranges(D ranges) are much more likely than they are for plants.
So things like GSA need lower ppm's of PO4 etc to grow and thrive.

Other species also do well in richer levels, or richer CO2, but not when plants are there or shading/growing and moving over time. But if you place a rock in there, they will slowly colonize.
If you a slower growing crustose GSA, it pays not grow in really rich nutrients.........grow only where good O2 is present etc......because you'd get covered with other algae species and they block the light/get all the nutrients etc.
If you are fast growing weedy algae, say like Spirogyra, you need high light, CO2(lower than plants, variable CO2 etc etc) and good nutrients.
You also need some spores to get started.

Each alga has a certain set of conditions for its niche.

Just make sure to apply Liebig's law to algae, not just plants, it'll help explain why adding more ferts does not lead to algae, or higher risk of algae.

Regards,
Tom Barr
 

Tom Barr

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Frank Lawler;54127 said:
Perhaps some of the suspicion is due to the fact that the exact mechanism by which a nutrient-filled tank can supress algae has never been explained. The standard reply that plants thereby outcompete algae seems somewhat incomplete.

This is a much larger question that most assume also.
It would apply separately to each algae species of interest, as well as each plant species, and at the individual, population and comminuity and ecosystem level.

That....is a lot of work about obscure aquatic plants and algae of little economic importance.
Only the weeds are in those groups. So only those get tested, algae is not much or a problem weed for many as far as control compared to aquatic plants anyway.
BGA's and some fish kills are related to algae and the blooms.

But overall, there's less $$$ for it.

So little research will get done.
Aquarist can falsify a few easier things themselves however.

Regards,
Tom Barr
 

ibanezfrelon

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Thanx for replying!

So what happens when folks stop adding ferts or add very little and they see improvements?
Well, again...........Liebig's Law also predicts a shift from say poor CO2 limitation(eg, they have high nutrients and also algae), and then say PO4 becomes more limiting.
This change from one limiting nutrient to another in terms of PLANTS, not anything to do with algae demands..............explains why this observation is true, but also why for many, that adding high nutrients in conjunction with good CO2........also has good results as well.
The naysayers do not have independent CO2.
Tom , so if i got this correct , if we can shift the plant limitation from limited co2 to limited say... ...PO4 , that would fix the algae issue even though the plant growth is stunted by low PO4?
Just as long as CO2 is not the one limiting the plant right?
Does this apply only to PO4 limitation , being the most gentile for the plant ? What about NO3 or K?

So if we can convince someone that lowering PO4 to moderate deficency has an indirect and not direct efect on algae growth , if we can explain to someone that lowering PO4 slows the growth rate so that now co2 is no longer limited , what could we name as downsides of such ''method''?
Because i think that a lot of people will find it easier to stop dosing PO4 than to maybe change the way they disolve co2 , or turn up the co2 etc..
I see a lot of tanks with high light and inadequate co2 , diy yeast systems with 1 lit or even 0,5 lit bottles that give a bubble every few seconds at best of times...
...so when those tanks have algae issues than all i can suggest to the person is lowering the light intensity and increase co2 what would sound very complicated , even expencive to some , because they wouldn't be able to reduce the light and don't have money for pressurised co2 sys..
Could in those cases reducing the PO4 to slow the growth rate and make the co2 non limiting be justified or the downside to this is too much? ..growth stunted too much or something?
..or maybe it's just too dificult to keep that limitation in C range?
 

Tom Barr

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Well, the question becomes, which limitation is worse?

Limiting PO4 or limiting CO2?

I'd say CO2 limitation is much worse.
Plants are much better able handle PO4 limitation.

The real issue is these people quite frankly..........stink at CO2 management that believe in PO4 limiting methods.
They often have low O2 also, or few fish. PO4 limitation is a reactionary response by aquarist, it has no real horticultural benefit or advances the knowledge base.
The CO2 is not independent.

They cannot test or provide an independent test to begin with, which is rubbish when they tell anyone in the hobby what is what or what is going on.
We know we have 2 very different observations, these are "facts" and they cannot both be correct.

I can induce the very same responses by manipulating CO2 when my PO4 and other nutrients are high, but have excellent results when not.
Met with this logic and observations, the PO4 limiting crowd has back tracked and hedged, PPS folks used this same line of crap, as have sediment only proponents........
They suggested that it is a good way to slow the rates of growth down or does not waste water or fertilizer.

1. Water/ferts are cheap, and if you limit them, then you are now limiting Light, which if you have seen your electric bill is much higher than any water bill in most homes.
Why waste light? Why not start where all growth starts and get a much better holistic philosophy with Horticulture??

2. Reducing light is a far superior method to reduce and control the rates of growth since it's the most stabkle parameter, and it's where all growth starts, including for algae.
It allows CO2 demand to be decreased, it's easy to adjust and measure if you have a light meter, it cost the most and reduces ALL WASTE including CO2 stress on fish/plants and less nutrients can be used.

I never understood how these high light people will poo poo nutrients in the water column, claim good CO2 ranges are bad, NEVER bother to test light, but claim testing ppm of PO4 or NO3 are critical and should be done, but outright guess everywhere else.
How can they whine about nutrients, act as if they are somehow much more "green"/Environmentally conscience or something and then WASTE lighting?

If the goal is truly about using less,less= better, then it should obviously start with lighting, but they wanna pick and chose, believing is some mythical high light low nutrient is best notion.
Tropica does not have incorrect, nor do I or researchers of Aquatic Botany. After 15 years of hobbyists vetting the principle........it's a bit silly to even argue these points.

Regards,
Tom Barr
 

Tom Barr

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ibanezfrelon;54170 said:
Thanx for replying!


Tom , so if i got this correct , if we can shift the plant limitation from limited co2 to limited say... ...PO4 , that would fix the algae issue even though the plant growth is stunted by low PO4?
Just as long as CO2 is not the one limiting the plant right?

Yes, pretty much.

Does this apply only to PO4 limitation , being the most gentile for the plant ? What about NO3 or K?

N will reduce growth and lead to BGA if you go too much, the main limiting factor is really PO4 for indirect CO2 effects on algae control.

So if we can convince someone that lowering PO4 to moderate deficency has an indirect and not direct efect on algae growth , if we can explain to someone that lowering PO4 slows the growth rate so that now co2 is no longer limited ,

Yes.

what could we name as downsides of such ''method''?
Because i think that a lot of people will find it easier to stop dosing PO4 than to maybe change the way they disolve co2 , or turn up the co2 etc..

True, it is simpler for some folks.
But it's bad horticulture:)

And, they are not correct in their rational why the algae goes away.
And the management of growth is far easier in the long term if the light is lowered.

They start off wrong from day one, too much light.

They also have a lot of issues for many, there are a few examples where they hit thr sweet spot, but most have trouble.

I see a lot of tanks with high light and inadequate co2 , diy yeast systems with 1 lit or even 0,5 lit bottles that give a bubble every few seconds at best of times...
...so when those tanks have algae issues than all i can suggest to the person is lowering the light intensity and increase co2 what would sound very complicated , even expencive to some , because they wouldn't be able to reduce the light and don't have money for pressurised co2 sys..

But they have the $$$ for high light?

This part I do not understand.

Could in those cases reducing the PO4 to slow the growth rate and make the co2 non limiting be justified or the downside to this is too much? ..growth stunted too much or something?
..or maybe it's just too dificult to keep that limitation in C range?

Well, people do not respect CO2, they are impatient, they fear nutrients, but do not fear or understand CO2, they think more is better when it comes to light, but all nutrients are bad like NO3, Fe, PO4, but Ca and K+ etc are "good".

These are social problems, not aquarium problems.

REGARDLESS if I chose an Ei method or a PO4 limiting PMDD method..............the results are more stable and better, easie rto manage no matter which method chosen if less light is used.
So that will resolve most things, then folks have more wiggle room no matter which method they chose and the management will be easier no matter what.

But these hobbyists want their cake and eat it too.
They do things diametrically opposed to their goals.

Meanwhile, I crank out plenty of nice tanks and sells lots of plants, shrimp and fish.

There's always a few often very vocal people who have CO2 issues for years.
They almost always have too much light and are cheap and impatient with CO2, a few are careful, but make bad assumptions about CO2.

So they claim they cannot fix the CO2 issues and they chose indirect methods.
They basically give up on mastering light, cO2 and nutrients and use just nutrients.
This does not promote good horticulture and they are hardly masters of aquatic horticulture.
They simply put; lack the control to do testing or mastery of CO2 itself.

So how can they teach others about CO2 well?




Regards,
Tom Barr
 

ibanezfrelon

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Thanx Tom , for answering my questions thoroughly , i find this very educational.

...and i will continue to spread the wisdom... :)
 

ibanezfrelon

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max yield concentration for Caldophora is 0.01ppm for CO2 and 0.001 for PO4, 0.01ppm for NO3
Are these actual numbers or approx?
Never thought the numbers to be so low..
Where could i find yield concentrations for other algaes? Do they differe much?
 

Wet

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I think you understand this but notice that those maximum yield numbers mean that limiting plants past their threshold (be it to remove the C limitation or what have you) still yields max yielding happy algae. While I am all for the balance promoted by good gardeners certain newer methods centered around limitation ignore this.

Another way to say this is anyone big on nutrient levels who ignores the biggest macro (C, which is most controllable via CO2, and we all know nutrient nerds are often too big on controlled doses) is doing it wrong. When approached with C as the biggest macro (by far), many nutrient nerds understand this pretty easily and rethink their tanks in my experience. This is good because it gets them to then think about what parts of "their" method match time proven methods. Those new adjustments usually gets folks moving forward on "their" variation of EI. I'm mostly talking off my stem plant people with at least moderate light to keep their tanks challenging and interesting.
 
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Ekrindul

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Fighting the "nutrients cause algae" myth gets harder this month. In the AquaticMaestro column of AFI this month, Paul Speice remarks, "And excess phosphorus causes algae blooms." Tom really should have a column in AFI as that magazine is far too entrenched in old myths and could use some fresh insight into the state of the hobby.
 

Tom Barr

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ibanezfrelon;54202 said:
Are these actual numbers or approx?
Never thought the numbers to be so low..
Where could i find yield concentrations for other algaes? Do they differe much?

These are from specific papers that sought answers to these questions in peer reviewed journals.
I can dig them up if I/you need........

So they are specific ppm's for those specific species.

Algae have a wide range, but most are less than Cladophora, which is a bit more like plants as far being larger, same chl 's etc.

Regards,
Tom Barr
 

Gilles

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Here's a good one, slightly O/T but still valid in this discussion: "Long stems are caused by to less light"
 

Tom Barr

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Ekrindul;58322 said:
Fighting the "nutrients cause algae" myth gets harder this month. In the AquaticMaestro column of AFI this month, Paul Speice remarks, "And excess phosphorus causes algae blooms." Tom really should have a column in AFI as that magazine is far too entrenched in old myths and could use some fresh insight into the state of the hobby.

Just send him a pic of my tank that gets 5ppm of PO4 as KH2PO4 3x a week.
Then let him defend his claims.

Even Einstein said all his life's work could be falisfied easily.

Regards,
Tom Barr
 

Tom Barr

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In general, let the person trying to defend such claims wrestle with the observations/results.

You need good observations where someone has added lots of PO4, or has low light etc.........and it helps to have the specific plant species in question and a nice scape is also helpful(Hopefully much nicer than the other poster's:cool:).

Then you just keep after them about it.

Do not be distracted with semantics or personal attacks.
Just stick to the topic and be relentless. We have plenty of aquarium examples to choose and pick from to illustrate the facts.

They feel they end up looking bad by insisting on the myths, not you.
So many take it personally. That is the source of the argumentative behavior.
A defense of their ego, not looking at the results or facts.

This is a social issue more than a plant issue.


Regards,
Tom Barr
 

Ekrindul

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Tom Barr;58354 said:
Just send him a pic of my tank that gets 5ppm of PO4 as KH2PO4 3x a week.
Then let him defend his claims.

Even Einstein said all his life's work could be falisfied easily.

Regards,
Tom Barr

I actually tried to email AFI concerning the article (there were other points he made that were suspect, ie. surface turbidity is a "no-no" due to deflection of light rays; that water changes can lead to algae blooms due to introduction of nutrients), but they seem to have some issue with their submission system.
 

Hallen

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A former believer of this myth right here, I even had my share in spreading it. Eventho I did it with good intend I still think back from time to time how much of a foolish greenhorn I was.

It wasn't until I got into reading and testing more and more, and still have ALOT to read/test,before I started to see the 'light' and literraly started playing with my lightning and nutrients which made me realise that high nutrients infact do not cause algae.

I was also very persistent in de Po4 myth due to wrong conclusions and reading it everywhere. It wasn't until I met Dutchy who asked the right questions before I could finally let it go for myself and find out the myth is false.

I will always remain skeptical, funny thing is at first I was very very skeptical to the Barr report and it's owner Tom. ''Who's this Tom guy claiming all the things?!'' that first impression quickly changed to ''Well dang, this stuff is very logical and has evidence. I should read more on what these guys have to say''. Right now I am a desciple spreading the word of Liebig's law, EI and 'low' lightning. I yet remain skeptical and eager to learn/test most of the things I read to make my own conclusions.