Check your Reef Crystals Salt!

[TimTen]

I got the info from the lab.

Sample #507

Salinity- 53mS

Alk- 13.1

Calcium Instant Ocean- 330

Magnesium- 1245

pH- 8.44

Temp- 72.7

 

[Ibn]

Looks like Kevin got the results back to you. Got mine a few days ago also, which differs from what Bob found.

Sample #403

Salinity- 53mS

Alk- 13.1

Calcium Instant Ocean- 375

Magnesium- 1335

pH- 8.55

Temp- 74.0

These are the results that I got from the same bucket from two different tests in regards to Ca and Mg...

Aquarium Systems Liveaquaria
Ca: 438 mg/l Ca: 375 mg/l
Mg: 1240 mg/l Mg: 1335 mg/l

 

[GreshamH]

OK I know who Bob is, but what Kevin are you spekaing of?

 

[Ibn]

Kevin Kohen from Liveaquaria/Drs. Foster & Smith.

 

[GreshamH]

Odd, wonder why Kevin is testing. He only deals with live stuff. Eric is in charge of the Dry goods.

 

[Ibn]

Don't know either.

 

[Mr. Ugly]

Aquarium Systems Liveaquaria
Ca: 438 mg/l Ca: 375 mg/l
Mg: 1240 mg/l Mg: 1335 mg/l

Hehe... this is what I got back.

Samples from 3 different orders.


ASI DF&S

Ca 423 Ca 330
Mg 1400 Mg 1230

Ca 380 Ca 345
Mg 1180 Mg 1230

Ca 411 Ca 360
Mg 1380 Mg 1245


I'll stick to relying on my own testing

 

[GreshamH]

huh, wonder why such a difference? What testing method is ASI using?

 

[iani]

That is insane. How can they have any sort of QC when the salts are testing that differently.

 

[Ibn]

I have no idea either. I asked Bob to provide me with his testing methods and equipment used. Got no replies after that. I also sent Kevin an email last night in regards to how his results differs from Bob's.

From my testing, I got Ca of 360 with Mg of 1170 with that bucket.

 

[GreshamH]

That's closer to what I got in one of my buckets. I had slightly higher numbers but the resolution of Elos got me 375ca and 1100mg. I still haven't heard back from Bob with his numbers on my 6 buckets. I guess I should send them off to Kevin as well.

 

[Mr. Ugly]

Yep, those are the kind of numbers I was getting as well.

Funny that our numbers are more consistent than theirs.

 

[GreshamH]

It doesn't help the highest numbers are from the manufacturer of the salt either

 

[Ibn]

Yup. Here's the reply from Kevin in regards to the differences.

Thank you for your email. Variations in the results obtained from testing seawater can be attributed to a multitude of circumstances. The first is the accuracy of each test kit. I am not privy to the types of testing equipment ASI is using, but would guarantee that these testing devices are far superior to what you and I use on a regular basis. Hobbyist’s grade test kits have a pretty large margin of error between brands, and even between two different kits of the same brand. We utilized a standard Salifert kit for your Magnesium Test and Instant Ocean titration kit for Calcium on your water sample.

The second factor that can affect test results is the exact specific gravity of the water. We calibrate a Conductivity meter prior to testing using a 53mS solution made by American Marine. The Calcium and Magnesium level of seawater varies considerably between 1.022-1.026. At a lower specific gravity, calcium and magnesium readings are substantially lower than at a higher specific gravity. Depending on the differences in the accuracy our meter vs. the exact specific gravity and accuracy of the meter used at ASI could also explain minor variations which would yield different results. To complicate matters further, using the same brand of test kit, one can test the calcium level of your aquarium six different times, and obtain six different readings. Normal protocol is to take multiple samples and test, adding the results together and dividing by the number of test performed to find a much more precise result.

 

[Mr. Ugly]

Heh, not surprised by the reply. Very generic, "It could be this... it could be that...." Just like if you'd call tech support and they ask, "Is it plugged in?"

I pretty much gave up on them both a while back based on the noncommittal replies I'd seen.

I was just waiting for both sets of test results to come back. I was expecting they'd have different numbers as well.

I'll just make my own test standards and go by my own tests. I got good repeatability when I tested my buckets.

Like I said, I kicked ass in quantitative analysis. I could always get 3 runs to agree within two tenths of a percent without a whole lot of effort.

 

[Ibn]

Yup, not really surprised either.

BTW, any chance that we can see some reference solution in the near future?

 

[Mr. Ugly]

I have alk and refractometer standards ready.

Have a few approaches to Ca/Mg that I want to check out, but those won't be for a while yet.

 

[MontanaBay]

Has anyone tested batches of IO lately? I'm curious what its numbers are testing at?

Many Thanks!

Josh

 

[chicken]

I am interested also. Just about to order another pallet of salt and do want to go through the whole swap out again with DF&S.

Thanks!

 

[Mr. Ugly]

Haven't tested IO in a long time.

Reef Crystals is still having problems. Check it out on the DF&S forum on RC.

Same old canned cover-your-butt answers from customer service too.

Almost 2 years later even. They should just give up already.