Plants and Algae

**vinz** · 19th Dec 2002, 16:35

Oh man... so much to read and say.

Allen, no I don't have a link as all this comes from various articles and forums all over web. I have also come to the conclusion that no one really has a good idea about what causes algae.

I agree about NO3, PO4 and alga. While the appearance of alga is often (if not always) accompanied by high levels of NO3 or PO4 or both. But having high levels of either or both does not necessary equate the presence of alga. However, more often then not, reducing these 2 to acceptable levels help to reduce and sometimes eradicate the algae.

As for alleopathy, I'm only speculating (which I thought was implied in my post).
Alleopathy is proven to exist and happen between plants, so why not against alga? For that matter, do some alga also practice chemical warfare against plants/other algae? Furthurmore, noticed that sometimes in a tank, alga appears on or near some plants plant but not others?

Now, the thing is, green algae is also a plant. Whatever plants need, alga need. So what keeps alga away when all their needs are present, or in excess in some cases, in a tank with healthy plant growth?

I think the key is to grow healthy plants. Give them all they need to grow well and they'll fight algae for you, be it by chemical warfare, by simply being better at grabbing nutrients. And not just sufficient fert (I include CO2 as a fert) and good light. We need to consider circulation, pH, temperature, etc., too. This is especially so for sensitive plants. At the same time, make things difficult for algae with nutrient control.

Side note: Alga = plural of algae. (I'm not being fussy about grammar... just thought some of you might like to know)

**geoffrey** · 19th Dec 2002, 16:49

----------------
On 12/19/2002 12:49:18 PM

----------------
I think CK is actually talking about the fluctuations in the nutrient levels forming an unstable environment in which the algae does do well. In addition, given that plants have an abundance of nutrients, then they can divert sufficient resources to alleochemical to suppress other plant growth.
----------------

Correct! But note that alleopathic chemicals do not only suppress algae growth, but growth of other plants as well. I think Ecology of planted aquarium pointed out Val and something... crypt?

The fluctuation theory is my own hypothesis lah. I dun intend to prove it with any scientific evidence (if that's what you are looking for). The idea is that it is not that algae no grow AT ALL, it is that they dun do as well as the plants, because the environment is not to its liking. So whatever minimium algae growth is taken care of by the herbivours.... sort of like, have you tried growing a certain plant (say R. macandra, or A. madagasxxx) and it just die on you. Why? You will probably say that the conditions are not to its liking although other plants grow like crazy. Same thing apply to algae I suppose.
ck
----------------

CK: To minimise those fluctuation we talk about, does that mean that once we have decided on our dosing regime, we stick to it and not flip-flop by adding more today and less tomorrow? And fickle-mindedly, switching between daily and weekly of certain element by changing their ppm accordingly?

**Allen_1971** · 19th Dec 2002, 16:58

---------------------
Side note: Alga = plural of algae. (I'm not being fussy about grammar... just thought some of you might like to know)
---------------------

Vinz,

You sure about that? I popped in to the merriam webster dictionary to check on the word Alga... the plural of alga is algae? Also, I was a bit surprised to find that Algae is pronouned like El-Gee and not El-Gay. Below is a cut and paste from the webby.

Main Entry: al·ga
Pronunciation: 'al-g&amp;
Function: noun
Inflected Form(s): plural al·gae /'al-(&quot

jE/; also algas

**vinz** · 19th Dec 2002, 17:12

Opps, think you're right. I took the entry on www.dictionary.com to mean 'plural is' instead of 'plural of'.

**vinz** · 19th Dec 2002, 17:18

Ehh... I think I know why my Valisneria are not doing. I just remembered reading (on The Krib, if I'm not wrong) that Valisneria don't do well in the same tank as Sagitarria due to alleopathy. But, someone on the forum has vals and sags in the same tank without adverse effects on either. Koah Fong if I'm not wrong.

**Allen_1971** · 19th Dec 2002, 17:21

Geoffrey,

The algae debate has been going on long before you or I have gotten into planted aquaria, and frankly no one has all the answers. Even CK's fluctuation theory is just that... a theory (at least for now...

).

There are several people who have done studies on algae, and from these typically have come out the guidelines to keep your Fe, PO4, and NO3 levels low... These as mentioned before are general guides, and should not be taken as infallible rules... There will be exceptions to this.

Generally a healthy aquarium with healthy plants and good nutrient balance should result in a relatively free of algae.

Having said that, I'm very glad this discussion came up

. Its given me the impetus to go read up on algae again, and allowed me to re-align quite a few of my preconceived notions on algae... some were right, some were wrong, and some were half right

.

**jacian** · 19th Dec 2002, 17:27

I agreed that in most case that it is a nutrient-limited tank that cause the outbreak of the algae. Then, why does with the presence of nutrients in the tank help to fight off the algae??

My guess on this:
Barley straw is known for its ability to combat algae. It is actually due to the Hydrogen Peroxide that it releases that kill off the algae. That's why some of us use H2O2 for algae treatment.

By keeping the plants healthy, be providing them the nutrients (including the lights, CO2) they need, photosynthesis will take place and the saturation of oxygen will increase in the tank.

I wonder if the saturation of oxygen has helped to combat algae. Maybe it has some form of oxidation effect as the H2O2, maybe by the action of our lights, some H2O2 are form in the water?

Comments?

**Allen_1971** · 19th Dec 2002, 17:27

----------------
On 12/19/2002 5:18:25 PM

Ehh... I think I know why my Valisneria are not doing. I just remembered reading (on The Krib, if I'm not wrong) that Valisneria don't do well in the same tank as Sagitarria due to alleopathy. But, someone on the forum has vals and sags in the same tank without adverse effects on either. Koah Fong if I'm not wrong.
----------------

Err yes I read the same too... theres supposed to be pretty strong alleopathy going on between Vals and Sags.... Was just at KF's place last night.. I noticed some Vals in the background... don't recall any Sags... but if there were some, I would guess the Sags are winning cuz the Vals are in bad shape

... (Due completely to alleochemical warfare of course

)

**budak** · 19th Dec 2002, 17:31

Red and green and blue and brown
flies the flag of algae town
rampant run we in tanks we shall
when nitrate blooms and phosphate swell

We fear not your finned armada
of ebi tiny or sucker baby
our brushes black shall sweep aside
all foes fat
and overfed.

Naught can stop our conquering march
though blue turns pale when erythro' strucked
time and again we crawl back in
like a swamp thing
in your bad dream.

**Allen_1971** · 19th Dec 2002, 17:33

----------------
On 12/19/2002 5:27:05 PM

I wonder if the saturation of oxygen has helped to combat algae. Maybe it has some form of oxidation effect as the H2O2, maybe by the action of our lights, some H2O2 are form in the water?
----------------

I'm a bit sceptical about that... I'm not sure whether H2O2 can form naturally in our water (though I think not)... but I think even if it could form, the levels required to combat algae, would also put your fish at risk.

Who knows though... High O2 levels are used in burn treatment to help recovery. I believe the skin grows faster (not sure). Perhaps it somehow helps the plants.... (Once again I'm just throwing out ideas... no scientific basis)

**Allen_1971** · 19th Dec 2002, 17:35

hahaha quite poetic hor budak! Is that how you woo-ed Mrs Budak? Muhahaha...

**geoffrey** · 19th Dec 2002, 17:37

So, finally we reach some consensus, healthy plants does minimise algae. Whew!
In my case, from now onwards, I will look at plants and not test-kits, as my guideline, to decide what they need. However, one can still embrace the notion of maintaining lower Fe, PO4 and NO3 to combat his own algae. Thanks everyone and let us have a Merry X'mas.

**Allen_1971** · 19th Dec 2002, 17:47

Hey Budak... heres my quick rebuttal

Stay your hand! Dreaded Alga Foes
For ye shall not triumph and bring me woe
Though I know not your weakness
or what makes you grow
I'll fight you with vigor
until you go

My nutrients are balanced
my plants in full bloom
So flee while you can
their alleochemicals loom
With Oto, Yamato, Siamensis and I
We'll sweep back your hordes
your advance we defy!

So &quot;NAY!&quot; we say
you'll not win today
For as long as we struggle
your clutches we stay
and sometime someday science will explain
the route, the path by which you are slain.

**bclee** · 19th Dec 2002, 18:46

Hey... you guys seemed to forget about NH3 as the N source. There has been argument that algae prefers NH3 over NO3 more than plants.

Another view point is that O2 toxicity inhibiting algae.

For me, PO4 is a lesser evil than most people have thought it to be.

Well... many theories... I guess there will never be a total agreement.

BC

**bclee** · 19th Dec 2002, 18:51

As for H2O2...it will become O2

2H2O2 --&gt; 2H2O + O2

High O2 is toxic to many organism. If I am not wrong, that may be the reason it is use as an anti-septic...

I am wondering if the high O2 content in the healthy planted tank is toxic to algae and thus stopping them?

BC

**CK Yeo** · 19th Dec 2002, 19:23

WOW! very amazed with the standard of English of some of the members here. [:0] can write poem on algae, can discuss how to pronouce &quot;algae&quot; WELL DONE! *applause*
Does the pronunciation of &quot;algae&quot; depends on which dictionary you look at; British-english or American-English, or Australian-English?

Ok. First I must clarify that I do not mean that algae die because of flactuating nutrient level. I believe that it is a combination of factors... a unstable nutrient level is only one of them. Cos I know there are people who dun do anything to their tanks and still it is algae-free. And also, there are people with PO4=0, NO3=0, but tank=BBA-infested.
Still have to look at other factors like CO2, light, stocking levels (bioload), alleopathy, among other things.

Then, regarding the &quot;barley straw produce H2O2&quot; theory, I think there are three papers that I found some years ago on this issue. All were published with relation to natural systems. The key factor is NOT H2O2 but phenolic compounds that are leeching out of the rotting plant material (from lignin, by bacteria???). Anyone has the latest reserach? Anyway, H202 is so reactive... I doubt it can last long enough in a enviroment full of organics to do enough damage to algae cells. so, what concentrations are produced? If H2O2 really is the key component, you might be better off dripping pure H2O2 into your tank.
Also I think O2 from plants are not reactive with H2O... I think it will have to be O radical... but that will cause more damage in the cell before it have a chance to get out.

So, there is no simple conclusion. We do not always know what cause algae. But we know a set of parameters we can follow and stick to in order to minimise algae growth.
Basically, it can be condensed into one simple phrase others have pointed out earlier...
&quot;Healthy plants = unhealthy algae&quot;
Now everyone say it with me...[

]

ck

**bclee** · 19th Dec 2002, 19:39

&quot;Healthy plants = unhealthy algae&quot;

Hey! it works! No more algae!!

BC[

]

**CK Yeo** · 19th Dec 2002, 19:42

H2O2 ---&gt; H20 + O

Theoratically, the extra O is unstable so it is highly reactive. While it can react with another free O to form O2, it can also react with other organics.
This is why it can be used as a anti-septic.

O2 is toxic? cannot say no but cannot say yes also. Dupla certainly thinks so. Amano also. Another complicated issue... For humans, it is the price to pay for being a oxygen utilizing organism; oxidative-damage. So a tank of happily bubbling algae will kill itself because there is too much oxygen?
The fact remains that we are far more successful getting rid of algae by ensuring plant grow healthy, not prevent algae growth at the expense of plant health.

ck

**TTL** · 19th Dec 2002, 19:45

HELP~!

I am being attacked by brown and tiny dots of green algae sticking at my glass tank especially the side.

I got 10 yamato and 2 Oto, but the yamato seem like they need ladder to eat those algae?

I suspect that it is due to poor water circulation? Pls help... I am very new in planted tank...

My config are;

CO2 1 bps
2 X 36W PL light
Overhead filter
1/2 of my tank is covered with plants
just prune three weeks ago.

BTW, why member do something like 4-5 hrs off light period during their daily 12 hrs of lighting?

**bclee** · 19th Dec 2002, 19:53

----------------
On 12/19/2002 7:42:52 PM

... So a tank of happily bubbling algae will kill itself because there is too much oxygen?

ck
----------------

You got a point... but Tom Barr thought so... he said he was going to study that... I am waiting to hear the results...

BC

Thread: Plants and Algae

Thread Tools

Bookmarks

Bookmarks

Posting Permissions