Differences in sand to prevent diatoms later

[Leroy]

I have a about 2 1/2 gal bucket of Southdown sand and cleaned it up and the sand feels like velvet. I know in the past the Southdown sand from HD was all the rage for reef tanks but has anyone suffered any diatoms as a result of the use of containing silica? I also have a 5 gal bucket of sand was that used in a reef tank but do very long and not sure how much silica it contains.

My question is, how's a good way to determine if sand passed on that is white in color not the HD "Play Sand" has any silica in it? Would it be best to examine it under a microscope or possibly a very good magnifying glass for any grains that look somewhat glass like in appearance?

OK doing a search I'm editing this and I found this result:
Vinegar is acidic and when it comes in contact with cal carb, like what's in aragonite sand, it fizzes. If it doesn't fizz it's a silica or quartz sand or some similar type sand.

 

[ReeferMedic]

Ron Shimek spoke at a meeting a couple of years back. I remember being involved in a conversation with him and a couple of brs members. One of the members asked him what he thought of silica sand and diatoms. His response was, "what is the glass your aquarium was built with from made from?" The answer was silica sand. IMO, it's one of those old wives tales that silica sand will contribute to diatoms. I would look first at how old my ro membrane is and go from there.