Originally Posted by Steve_
Originally Posted by Pat Williamson
Steve I think it would do some good now but you need to take a water sample and see what you got to start with. Mine was cloudy and it started to clear up in a few weeks

Thanks Pat. Forgot to mention that my pH is in the low to mid 5's. Does acidity affect turbidity directly?

Does acidity affect turbidity directly? Yes and no.

Nature can grind sand grains finer and finer. From beach sand, to silt sized, all of the way down to some of the dust motes you see floating in the air in your house. However, sand (SiO2) is basically inert, regardless of the size.

Clay is the geologic term for an entire class of complex phyllosilicate minerals that display a wide range of interesting chemical and physical properties. Unfortunately, the very smallest size on the sediment grain-size chart is ALSO called clay.

THIS IS VERY CONFUSING! We use the same term for two separate concepts.

"Clay" on the sediment size chart means a particle that is less than .004 mm in size. "Clay" should more properly be used as the term to describe an entire class of minerals.

My best analogy is the person that calls every tiny fish a minnow. On Pond Boss, we know that it really matters if the tiny fish is a FHM or a green sunfish fry!

For this discussion, don't think of clay as tiny sand, think of it as a very special kind of tiny fish.

You cannot build a functional core seal in your dam by crushing and compacting sand grains. The wet sand grains will not form a ball in your hand, no matter what their size. However, wet clay grains will form a ball, and will lock together to make a sealed core in the dam due to the specific physical/chemical properties of clay minerals.

Finally addressing your question:

If the suspended "clay" in your jar will settle out in a reasonable time, then it is probably mostly clay-sized INERT sand grains. (*** At tiny sizes, even "inert" particles can have electrical surface charges, but let's skip that further caveat.)

If the suspended "clay" in your jar will NOT settle out, then it is probably particles of clay minerals that actually have a weak surface electrical charge. These are usually negative charges - and they are attracting the positive ions in your water. (Your low pH water definitely has positive ions.)

The positive ions are attracted to the negative charges on your clay particles and create a kind of "cloud" around each individual particle. These clouds push away the adjacent positive clouds surrounding other clay particles. (Like when you were a kid and tried to push two magnets together with the same poles touching.)

The best way to get actual clay mineral suspensions to settle out is to get the tiny particles to be attracted to each other and clump together. This is called flocculation. If you change the water chemistry (by adding lime) you can change the properties of the suspended particles and cause them to flocculate. [Basic (high pH) water chemistries would utilize alum to cause flocculation.]

*** Sorry for the very long post. I started typing a "brief" response, but my answer always seemed incomplete without additional background information. I decided to go ahead and make it long, because lots of people ask your same question!