[Zapins]

If you are interested in BBA and DOC then read through this thread: http://www.aquaticplantcentral.com/forumapc/algae/89126-organics-analysis.html, a table of results starts on page 7 if you'd rather skip ahead to the data.

We are collecting data on it and hopefully one day will finish the experiment and figure out what the relationship is.

 

[Zapins]

JeffyFunk was running all the samples, but the last I heard his DOC analyzer broke and was being repaired. I do not know if it has been fixed yet. I hope he can still run more samples to finish the experiment. We still need another 15 or so samples before I can run the stats on it for a meaningful result.

 

[Zapins]

Zorfox - how are we sure that CO2 causes or contributes to BBA?

From what I've been able to gather from the data in the APC thread it seems more common in tanks where CO2 is injected. If our hypothesis says CO2 will stop BBA from growing then that is 100% proven false simply by its presence in more than 50% of the high tech CO2 results we collected.

Perhaps CO2 lessens the extent of BBA? But then why would it seems to grow on filter outlets, and on CO2 diffusers? The old advice that low CO2 = BBA simply isn't right based on the data we have.

At one point many years ago I had a really bad BBA outbreak, so I removed all my fish and added so much CO2 my water fizzed like soda for weeks. The BBA grew on every surface like I've never seen it grow before, so if anything I'd say it seems to promote growth.

 

[Zapins]

The problem I have with algae advice that says "this definitely causes that species of algae to grow/die" is that there are a hundred examples that support and a hundred examples that refute the statement. I strongly feel we should not say that we know 100% what causes a species of algae to grow or not grow without conducting proper trials and running the correct statistics on it. Without going through the proper steps we can't claim 100% knowledge of what causes a given algae. There will always be hundreds of counter examples and people who believe they know what causes it until we have solid well conducted experiments and numerical data to back it up. The best we can do until then is make educated guesses based on our personal experience which may or may not work for anyone else.

Whatever causes each species of algae to bloom can't be related simply to one factor, otherwise we'd have figured it out by now and never have algae issues.

My problem with blaming CO2 stability, fluctuations etc.. for BBA is that we cannot accurately, cheaply, or reliably measure CO2, or even measure how much BBA we have in a tank. This makes figuring out if CO2 is related or not very difficult at the hobbyist level.

 

[Zapins]

I built a CO2 sensor for my arduino for $250. Pricey but affordable. The trick is to making it waterproof which I failed in the long run.

Now this is interesting.

Do you have a thread on how you built yours?

Any idea how accurate the probe is?

They sell CO2 detectors for rooms, but they are only accurate to within 5-10% which isn't very good IMO.