CaSO4 vs K2SO4

[BenB]

I bought and just received some K2SO4 from a vendor.
When I opened it, it was soft and fluffy like flour. There is no visiable particle or gain Every time I've bought K, it has been small grainy like sand.
I'm wondering if I didn't get mislabeled CaSO4. It looks and smells like it Ca, but when I've bought Ca, it has been smooth white with some chunks.
Is this a high grade of K that I've never had before, or has yours always been grainy too and I should write the vendor?

 

[ElleDee]

If you have a GH test you can add some to water and see if it increases or not. That wouldn't tell you that is was K2SO4, but you could exclude something with calcium.

 

[SkaleyAquatics]

I bought and just received some K2SO4 from a vendor.
When I opened it, it was soft and fluffy like flour. There is no visiable particle or gain Every time I've bought K, it has been small grainy like sand.
I'm wondering if I didn't get mislabeled CaSO4. It looks and smells like it Ca, but when I've bought Ca, it has been smooth white with some chunks.
Is this a high grade of K that I've never had before, or has yours always been grainy too and I should write the vendor?

Is this from nilocg? Because I bought my original batch from gla and it was grainy. Bought a bunch of k2so4 from nilocg cause bulk and mine came in the same way. Honestly I never questioned it. And plants are not potassium deficient so I never gave it a second thought. Same thing happened with Kh2Po4, again haven't had an issue with it.

 

[BenB]

If you have a GH test you can add some to water and see if it increases or not. That wouldn't tell you that is was K2SO4, but you could exclude something with calcium.

I had thought about this, but I was trying to be lazy.

Is this from nilocg? Because I bought my original batch from gla and it was grainy. Bought a bunch of k2so4 from nilocg cause bulk and mine came in the same way. Honestly I never questioned it. And plants are not potassium deficient so I never gave it a second thought. Same thing happened with Kh2Po4, again haven't had an issue with it.

Yeah it is. That's why I'm curious. It could be a very high grade. I haven't used it yet. My current fert mix has ~20ppm K from the KNO3 and the KH2PO4, so it might take awhile anyway to show K deficiency for me. I'm not sure what you dose.

Another thought is that, in my experience, CaSO4 dissolves slowly. K2SO4 dissolves quickly. If I put a bit in a test tube, it might give me a hint.
We should both attempt ElleDee's suggestion.

 

[BenB]

I did the test
I put a tiny bit into a tube with some distilled water and my GH was 7.
It dissolved right away, so I thought it was K. Usually Ca sits there a bit.
I guess I'll be writing him.