Algae/Green Water Myths and Theorys

TCLynx

Here is a link that mylesau originally posted in his aquaponic swimming pool thread
http://koiclubsandiego.org/library/green_water.php

It seems to have explained much of what I have seen without knowing exactly why. It is a site more related to Koi keeping but the info and experiments relate to aquaponics.

Here is a quick quote from that web page.

Quote:

When algae dies and is subjected to aerobic bacterial decomposition by heterotroph bacteria, a by-product of this process is a substance, released into the water, that is toxic to the living algae.

There is another reason to have media filled flood and drain grow beds, ample space for the heterotroph bacteria colonies to break down the solids and control algae.

RupertofOZ

Too true TCL.... heterotroph bacteria colonies to break down the solids and control algae was an issue discussed way back in the early days of the forum....

As you say ... another benefit of media filled growbeds....

scottt

Bit of a long read, but interesting.
I like this line

Quote:

I left this for the very last so that all the die hards who managed to read all the way through this thing can consider the implications, draw their own conclusions, and realize how many new questions it raises.

Rons_Place

scottt wrote:

Bit of a long read, but interesting.
I like this line

Quote:

I left this for the very last so that all the die hards who managed to read all the way through this thing can consider the implications, draw their own conclusions, and realize how many new questions it raises.

Hmmm Wouldn't work with me, I read the Title, the 2nd to last and last page and if it appears interesting only then will I read the journey to get there.

Quote:

I left this for the very last so that all the die hards who managed to read all the way through this thing can consider the implications, draw their own conclusions, and realize how many new questions it raises.

This sort of line tells me it's not finished so whats the point in only reading 1/2 a story.
:twisted:

Cheers
Ron

steve

Ron, i think its just as important to highlight why you think some info is incorrect even when you dont have the correct answer. i think thats why he might have written it.

LOL, happens all the time with conspiracy theories, some how the burden of proof end up being for you to give "what happened then?" when all you're trying to say is "what didn't happen"

My water went form visibility of a few cms two days ago to "murky" last night to CRYSTAL CLEAR tonight.

EllKayBee

Quote:

My water went form visibility of a few cms two days ago to "murky" last night...

What you need is a few fresh water mussels mate

RupertofOZ

any muscles would be an improvement for Steve Elk..... :lol:

Dufflight

My pool has gone green. I'm working on the muscles.

steve

you misinterpreted, murky has much higher vis than a few cms

Dufflight

I can see for about a foot. And there is a lot of green particles. The skimmer box has been collecting green foam.

Sleepe

I read this article with interest. I disagree with some of the 'myths' and the theory is unproven.
I assume that the author is talking about algae and not for example cyanobacteria.
Light quality, temperature, and nutrient load do play a part in algae growth. As do the numbers of zooplankton in the system.
Allelochemicals, which I assume are the magic bullet, do not usually kill they do however interfere with growth and can prevent growth of new cells. The only effective natural producers of allelochemicals I know of (in water) are macrophytes. An exception to this are death in large numbers of the cyanobacteria (which are called blue green algae) which are toxic. In an AP system what is not clear is the effect plant roots have on algae (higher plants produce various allelochemicals).
The theory that hetrotrophic bacteria by destruction of dead algae produce allelochemicals seems unlikely. Someone can correct me on this but my understanding is that besides mineralisation they create (ammonia?) co2 and dissolved organics into the water. This I would have thought would be a benefit to algae and bacteria. Barley straw might produce allelochemicals however the only study I found suggested that a phosphorus depletion in the water was the greatest effect in reducing algae numbers.
Nevertheless it was an interesting read and the results merit further investigation

My two cents worth anyway

TCLynx

As far as an article that shares some common myths as to why algae blooms happen and then shares some experiments done on algae samples with different water and then ventures a few theories as to why they think this might have happened. I thought it was good as far as it went.

It certainly seems to fit. Remember it isn't the barley plant creating whatever makes the barley straw work against algae, it is the aerobic decomposition of the barley straw in water that seems effective at controlling algae.

Whatever the specific reason that a system with ample bio filter space seems to get past the pea soup stage, it does seem to work. I suppose it is possible that there is some plant (that is responsible) really common to all healthy established koi ponds that don't have the pea soup problem and arn't using chemicals or ultraviolet to keep it away but that probably wouldn't explain why AP systems seem to fit this guy's theory.

I avoided the initial pea soup problem by shading my water like 90%. Early on I noticed lots of algae growing on all surfaces where there was light available but now the algae is mostly died off and I don't seem able to get more to grow in the system even when I try. It used to be a real treat to scrape algae off the water fall for the tilapia but there is almost no algae there anymore.

steve

the addition of algae to % mature water test jars would seem to support the allelopathy premise, especially if they were using pure water as the solute.

Also i think the article seems to relate more to the suspended algae versus the "clingy grow on the side type"

creative1

What water temps in the FT have you got TCL?
Just wondering if it is too warm.

steve

all this talk about allelopathy tug at a bit of stored info, a quick search on the web and a peek outside showed a great deal of luck in planting the black walnut tree with the greatest spacing from all others fruit trees i just planted! phew.

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