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post #1 of (permalink) Old 01-04-2013, 12:08 AM Thread Starter
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Join Date: Jun 2004
Location: Baton Rouge, LA
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AlgaeFix: Experiences, Experiments, and Thoughts

As described in the title. I think it's worth sharing. If you prefer a briefer read, scroll down to the "Thoughts" section to see the real meat of this article - which describes how AlgaeFix works, why I believe it presents a risk to livestock, and how that risk can easily be reduced.


My first experience was an overwhelmingly negative one.

I had an incurable case of severe green water in a certain tank, that persisted for months. Believe me when I say incurable! I tried everything. I've easily beat green water in other tanks, but not this one. The only thing that had any real effect was continuous diatom filtration, and it came right back when discontinued.

I heard AlgaeFix worked wonders on green water. So as a last resort I tried it. Within minutes, every guppy in the tank was stunned; drifting without control, with periodic bursts of erratic movement. I performed massive water changes. Some recovered, some died. The green water was slightly reduced, but recovered quickly; the AlgaeFix was obviously effective, but the exposure was too brief.

I checked my dosage, and was sure I hadn't overdosed. Normally I would have thrown the bottle straight into the trash, but desperation makes you do funny things. So I tried again, but this time with a half dose.

This time, some of the guppies soon showed mild respiratory distress. Like in a tank with too little oxygen, or too much CO2. I kept an eagle eye on them over the course of the next few hours, ready to perform another massive water change should symptoms worsen. But instead, they recovered fully. The green water did not, and was finally gone - never to return after that single half dose.

I found that curious. So I searched extensively for other people's experiences. Most reported no issues. A minority, but still a significant number, reported problems like mine.

I also found some suggested that when a massive amount of algae is rapidly killed, as you'd expect with green water, that this results in equally rapid oxygen depletion. Makes sense, but it didn't seem like a perfect explanation.

I killed more algae with the second reduced dose, yet it had far less effect on the fish than the first. Others had killed equally massive green water blooms with the full dose, without issue. And some had used it with only minor algae of other types, yet had fish deaths. This explanation didn't quite fit.


A year went by, and still I wondered about this. I did some more research, and then it was time for an experiment.

I crossed my fingers and added a full dose of AlgaeFix to a different, healthy tank, with no green water or other types of algae. Mild and temporary respiratory distress again occurred in a few fish, disappearing in an hour or two. Perhaps oxygen depletion due to dying algae partially explained my first awful experience, but as there was no algae this time, there shouldn't have been any respiratory distress.

I waited a few weeks, did a few water changes. Tried the full dose again, same temporary respiratory distress. Apparently whatever negative effect AlgaeFix was having is something the fish could adapt to.

A few more weeks, and a few more water changes. This time, I added the full dose, but split it into quarter doses, spread out throughout the day. No symptoms of respiratory distress at all.


The active ingredient of AlgaeFix, Busan 77, is a surfactant. In more familiar terms, it's similar to soap; though this isn't a perfectly accurate comparison.

It alters the surface tension of water, and enhances its wetting properties. Both of these affect the exchange of gasses, water, and other chemicals transfer across semi-permeable membranes, like those that encapsulate cells.

The method by which it kills algae is known. With the properties of water altered, excess water moves into the algal cells faster than they can eliminate it. The end result is that the algal cells, being rather rigid, literally burst.

Now doesn't that sound like it would also have some effect on gills? I certainly think it does.

My Googling has been less than satisfactory, as many of the relevant papers are on sites that require money to access. But this much I have been able to find:

Gills (and lungs) make their own surfactants. They are an essential mechanism by which they self-regulate gas exchange and other processes. Exposure to additional surfactants does disrupt O2 exchange, though I can't find whether it increases or decreases it. It does increase the absorption of many other chemicals, and surfactants are often used explicitly for this purpose.

Maybe others can provide other details.

Regardless, I find sufficient evidence to believe that adding a full dose of AlgaeFix, all at once, is a stressful event for fauna. Whether that stress is small enough to go unnoticed, or big enough to cause deaths, depends partially on other factors like dissolved oxygen content.

But in all cases the stress can be reduced by dividing doses up into smaller doses with a few hours between each, which gives fauna time to adapt.

This doesn't seem to change its effectiveness on algae. Though I admit I have little experience here, as I still consider AlgaeFix a method of last resort, at least in a tank. My favorite use is in a bucket, as a plant dip to remove algae.

That's all. If you have your own experiences, experiments, and thoughts, please share!
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