Trying to identify additive

[LoneStarPool]

I'm going through the stuff left by the previous owner. In a bucket with a picture of chlorine tablets on it, I found the following substance. It doesn't have any odor, and has a consistency of flour. Is it safe to assume it's just DE (Diatomaceous Earth) I can use for my filter? Here's a pic:

 

[YippeeSkippy]

Personally, I'd toss it. It might be calcium or anything? If not labeled clearly you don't need that kind of chance. YMMV.

Maddie

 

[LoneStarPool]

Is there an easy way to tell the two apart? I've been cruising on the supplies he left behind since I got the house, and it's the only one I couldn't identify.

 

[YippeeSkippy]

Well, if its calcium you can take a bit and pour some muriatic acid (maybe vinegar too?) on it and if it fizzes that would highly suggest its calcium. If its Borax, I don't know how to test that? If its garden DE it won't work in your filter, as it requires POOL DE

 

[HermanTX]

I'm going through the stuff left by the previous owner. In a bucket with a picture of chlorine tablets on it, I found the following substance. It doesn't have any odor, and has a consistency of flour. Is it safe to assume it's just DE (Diatomaceous Earth) I can use for my filter? Here's a pic:
View attachment 647962

I agree with @YippeeSkippy If it is not correctly labeled then it should be tossed.
DE normally comes in a heavy duty bag (paper or plastic). Not sure why they would transfer it to a plastic bucket and not label it properly.
It looks like DE because it is like confection sugar (i.e. powdered sugar). Not sure how to test it.