Gravel Unknown composition

[Heelllooo]

Hello I have this gravel laying around at home.

https://www.coeck.be/fr-be/catalog/3261/499?cref=3067

I want to sprinckle some on a clear pool filter sand for a 10L blue velvet neocaridina setup that i'm working on.

I know it come from the Rhine but i just can't find any information on the chemical composition of this product and the seller is closed until end of the month of course.

Any ideas what it's made of ? Is it inert ?

I will not using much so if it's only releasing a bit of calcium or carbohydrate i would not care.

 

[Hufsa]

There are many ways you could test the stones, some are easier and require less materials than others.
You could for instance put some of the gravel in a jar with RO water and see how much the water changes after a few weeks.
If you have access to measuring TDS, conductivity, GH or KH they would all give you an indicator of before and after.
If youre only concerned if it will release a lot of something, you could swap the RO water in the test for aquarium water instead.
If you had to make sure it definitely didnt release anything, a stronger acid would be a better test, but in your case it seems you dont require it to be 100% inert.
Youre setting up a Neocaridina tank, so odds are you will have a decent level of KH and GH in that tank anyway