I posted a while back that I was trying to see if I could culture my own fresh spirulina, but after letting the whole setup sit for about a week, it is clear that it failed.

This isn’t a bad thing. It was only an experiment, and as I wrote when I started, there was evidence that the spirulina in the paste wasn’t active. So when I try again, the first thing to change is to find an active source of spirulina that I can try again with.

Here is a record (mostly for my own purposes) of the failure…

The culture became less and less green over the course of the week:

So I decided to look at a sample under the microscope, and I didn’t see any cells at all. (I didn’t include a picture since there wasn’t anything to see.) My theory is that all of the spirulina cells in the sample broke apart and the yellowish green is actually just the chemicals that came out.

The other thing I tried is a new water quality analyzer I ordered a few months ago and finally arrived in time to take a measurement of the failed experiment.

It has three probes that you drop into the solution you want to analyze:

From top to bottom, these probes are for the total dissolved solids (measured using electrical conductivity), the pH probe, and a temperature sensor. In case you are wondering why the device says “TRI-METER, Six in one monitor”, this is really a case of wishful thinking on the part of the manufacturer. It measures the three quantities I mentioned above, but they are counting it as six because it can show these three quantities in different units (EC, CF, PPM for the electrical conductivity, pH, and temperature in Celsius and Fahrenheit). So the “tri-meter” is accurate, and the “six in one” can be ignored. :-

Anyway, it costs about $60 on eBay and is powered by a built in rechargeable battery. Unfortunately, the charger is 110V (Thailand is 220V AC), but fortunately the plug is just a USB connector. Unfortunately again, the charger connector required is a USB type A male which is not common in a USB charger.

So I ordered a USB type A male to type A male cable that I can use to charge this from any normal USB charger (or computer USB port).

First thing I did was to test it by dropping the probes into a glass of filtered water:

The pH is 7.13 which is pretty close to what you’d expect, and the electrical conductivity is 0.25, which comes out to about 125 PPM, which is well below the 500 PPM you see as a general guideline for drinking water. And the temperature of 29.5 C is basically what you’d expect on a Bangkok morning in March.

Moving on to the spirulina culture:

You can see the pH is 8.79, which might be reasonable since spirulina likes very high pH values (9 and up) but other algae don’t, so the culture medium is supposed to have a high pH. The TDS of 13600 PPM is quite high, of course, but you could pretty much see that from the murkiness of the container.

Anyway, I’m going to put this experiment down for a little while until the other things I am working on settle down. But I’m still eating (store bought) fresh spirulina paste mixed with lime and fresh made apple juice nearly every morning so I will almost certainly come back to this when I have more time to focus on it.

Until then…