Anyone else see Reef Crystals mixing at 7.5dkh?

[Joe31415]

Any time I've ever tested my water change water, Reef Crystals have always had a surprisingly high alkalinity. Usually over 13. It's always been this way and I know it's supposed to be this way. However, for at least the last few bags I've used, possibly even the previous box (I don't remember how long ago it started), they've been under 8.
Just today, when I tested it, I got 7.46 with the Trident and 7.7 with Hanna.
I don't think this is an issue with the new salt separating. It's happened over multiple bags. I use bags, not a bucket. I try to shake it up before I open a bag. It's been consistently under 8. And, on top of all that, it seems to me that if the low alkalinity was due to it separating in the bag, I should also have some batches that test well over 13.

That's wrong, right?

 

[Tritie]

I did not test alk, but tested mag with Aqua Forest 1x and Red Sea 2x (within expiry date) and I got 1050ppm. I was not happy.

 

[Aaron75]

How sure are you that your salinity is correct? That's the only time I've seen #'s outside my expected range.

 

[fishface NJ]

Did a water change yesterday. Mine mixed to 7...using Salifert test.
I used a Tropic Marin hydrometer

 

[cobraz]

Yes Alk haz been very low in the latest 2 buckets I have used..I have even mixed the salt in the bucket before adding it to water still 7 to 8 max. My last bucket has been slightly higher at 8.57.

 

[cobraz]

Here is a chart with recent testing..there are more brands but I narrowed it to TM Pro, Reef Crystals and AccurSea.. interesting Par vs Price.

 

[Euphylliaphyle]

I just tested some freshly-mixed Reef Crystals in RO/DI using Salifert titration:

Ca: 455
Alk: 7.5
Mn: 1,160

Lot 19235 22:18

Mixed to 35 ppt using Tropic Marin glass bulb hydrometer and temperature-corrected.