Tyndall Effect [The Laser Beam Test]

Tyndall Effect
By Ode Coyote

Since the human eye can detect a single photon but doesn't have the resolution to distinguish between them, laser TE can tell you many things much like a particle sizer works, but without calibration, the visual effects can only be generalized as a "feel" for size and quantity.

"Brightness" is total reflective surface area density, regardless of particle sizes with high colloid content being brighter than low.
That's an indication of "How Much" vs what size..

Ions are too small for visible light to reflect from, so they are invisible...it's also possible to have particles below the ability to reflect light in the visible wavelengths, hence also be invisible.

A distinctly fuzzy appearance to the beam indicates that the dominant particle sizes are too small to reflect a photon stream large enough for your eye to distinguish between streams..very small particles just over visible light size ranges. [less than 5/10th micron as an "eddycated" guess]

The next effect towards larger particles will be a sort of sharpness to the beam that says you are very close to being able to distinguish between photon streams. [ ~.5 to 1 micron as a good guess ]
Fuzzy and sharp can be mixed and you can tell when they are..that they are, but not where anything ends or starts.

If you can apprehend individual bright spots, that's the next size range up. These will probably settle out in a few days and are probably about ~1-2 microns in diameter.

Then there's the "stars" aka "sparklies" Most of those are harmless electrode sludge silver hydroxides, essentially waste matter and will settle out in a few hours, yet are small enough that nothing but a really good lab filter will catch them all.

Then "chunkies" or Silver Hydroxide [electrode sludge] clusters that immediately hit bottom. They look like asteroids.

Generally, you'll see a fuzzy [velvety] backdrop with all the other effects at first, in different comparative degrees, then in a few days, nothing but fuzzy to fuzzy/sharp.
Anything bigger than that settles out on its own.

Also, TE doesn't usually start becoming apparent in a stirred current controlled system until around 10-13 uS ionic has been reached. There is another threshold at around 25-30 uS
 But once a particle is made, it doesn't tend to unmake itself and there are many environmental reasons a particle can form that have nothing to do with how the generator is working.

"Particles" are not detectable with a meter...but they still contain silver, adding to total PPM.