Salt batch issues

Smallslandreefer · Jan 10, 2024

Hey guys,
Have some issues with aquaforest reef salt. I checked the batch number and at 33 ppt salinity the alk should be around 7.6 dkh. I mixed a 20 litres yesterday at 35 ppt and tested alk today with ati kh and salifert. It came up at 6.4 dkh. Why is that some slat bacthes come low on dkh. Should in not use it? I can fix the alk with some baking soda but i am worried that other parameters (elements) might be at different levels from the ones the batch icp refers. Any opinions and experiences. Should i take it back to my LFS?

CasperOe · Jan 10, 2024

Nah just use it! Remember, your test kits have some error attached to them as well!

It may serve as a good practice session on ensuring consistently having the same test results. There may be some array of user error attached to this as well. Try testing five times in a row using your test kit. If you are using it correctly and consistently, chances are you will have very similar results from each test.

What I am trying to say, there's nothing wrong with your salt. Go ahead and use it - and if you really want to know "the exact alkalinity", take the average of your five tests.

Dburr1014 · Jan 10, 2024

Smallslandreefer said:
Hey guys,
Have some issues with aquaforest reef salt. I checked the batch number and at 33 ppt salinity the alk should be around 7.6 dkh. I mixed a 20 litres yesterday at 35 ppt and tested alk today with ati kh and salifert. It came up at 6.4 dkh. Why is that some slat bacthes come low on dkh. Should in not use it? I can fix the alk with some baking soda but i am worried that other parameters (elements) might be at different levels from the ones the batch icp refers. Any opinions and experiences. Should i take it back to my LFS?

I'd use it.
Did you mix the bucket before mixing with water? Some things settle out in shipping.

Randy Holmes-Farley · Jan 10, 2024

I agree, I'd use it. There are lots of sources of error in your measurements, including both the salinity and the alk testing, and how well you adequately sampled the entire bucket.

I'd also take batch info to really be their target for a bucket, not what actually shows up in every single bucket.

Smallslandreefer · Sep 10, 2024

What i found it is the a very small (pinch) amount of baking soda in the RO water prior to mixing it with the salt keeps my kh from decreasing while mixing. I don’t know exactly why is that but i assume it has something to do with the RO not having any dissolved solids prior to mixing the salt making it more prone to alk precipitation. Once i add some baking soda my alk is near my desired level however i dont know if this affects anything else apart from ph and alk in the mix. Where i live there is alot of humidity and heat(which i think plays a role) and i rearly get the dkh at the desired level still dont know the true reason but fortunately baking soda seems to do the trick

Randy Holmes-Farley · Sep 10, 2024

Smallslandreefer said:
What i found it is the a very small (pinch) amount of baking soda in the RO water prior to mixing it with the salt keeps my kh from decreasing while mixing. I don’t know exactly why is that but i assume it has something to do with the RO not having any dissolved solids prior to mixing the salt making it more prone to alk precipitation. Once i add some baking soda my alk is near my desired level however i dont know if this affects anything else apart from ph and alk in the mix. Where i live there is alot of humidity and heat(which i think plays a role) and i rearly get the dkh at the desired level still dont know the true reason but fortunately baking soda seems to do the trick

That implies the salt mix is low in alk. It is not because of any issue related to the ro/di.