IO Reef Crystals confusing Alk reading

[JasonVH]

Mixed 5 gal of fresh IO Reef Crystals in plastic bucket with powerhead through last night.

Refractometer is reading at 1.026.

Tested Alk from it just now. Hanna gives 5.8.

Salifert gives 6.1 for when the blue starts to change to dark purple. 6.7 when the pink starts to appear(pink tinted with purple).

That seems much lower than the usual comment or charts for this brand- most commonly at/around 11.

I'm confused. What's going on or am I missing something?

 

[Aaron75]

Make sure your salinity is correct. Easy to blame a relatively cheap salt brand but when i had an Alk issue (too high) it was because my calibration solution was off so my refractometer was off. I was mixing to like 1.035 instead and my Alk was almost 12.

 

[JasonVH]

Make sure your salinity is correct. Easy to blame a relatively cheap salt brand but when i had an Alk issue (too high) it was because my calibration solution was off so my refractometer was off. I was mixing to like 1.035 instead and my Alk was almost 12.

I do have the BRS Refracto Juice- is it considered 'reliable'? I'll use it and check right now.

 

[rhitee93]

Your numbers seem quite low, so measurement error of some sort is something you need to rule out.

However, I will say that I use reef crystals, and my alkalinity is never anywhere near 11dkh. When mixed to a SG of 1.026 I see 8 to 9.

 

[JasonVH]

Your numbers seem quite low, so measurement error of some sort is something you need to rule out.

However, I will say that I use reef crystals, and my alkalinity is never anywhere near 11dkh. When mixed to a SG of 1.026 I see 8 to 9.

Yeah I am considering that as a possibility. The low readings from both Hanna and Salifert is throwing me off. What else can I try? Thinking of doing a couple more tests with both Hanna and Salifert to see if they come out consistently... if they do, what then?

Appreciate the feedback- also the results of your own mixing.

 

[Aaron75]

I do have the BRS Refracto Juice- is it considered 'reliable'? I'll use it and check right now.

Obviously calibrate it with what you have and see if that makes a difference. If not, you can make your own calibration solution.

 

[Randy Holmes-Farley Verified Community Expert]

Yeah I am considering that as a possibility. The low readings from both Hanna and Salifert is throwing me off. What else can I try? Thinking of doing a couple more tests with both Hanna and Salifert to see if they come out consistently... if they do, what then?

Appreciate the feedback- also the results of your own mixing.

Is there any precipitated solid remaining after dissolution of the salt?

Are you sure you are reading the Salifert scale correctly? To check that, if you used most of a syringe to get to the color change, that’s high alk, not low. Many people read it backwards.

 

[JasonVH]

Make sure your salinity is correct. Easy to blame a relatively cheap salt brand but when i had an Alk issue (too high) it was because my calibration solution was off so my refractometer was off. I was mixing to like 1.035 instead and my Alk was almost 12.

Update- BRS refracto juice + a minute or so wait(says wait 40 secs as per instructions) gives reading of almost 1.029....

(edit- never mind this part- you answered it already, thanks!)There's a bunch of wildly divergent reviews on various refractometer calibration fluids. How do I tell if that's the true calibration or it's the fluid that's off?

 

[JasonVH]

Is there any precipitated solid remaining after dissolution of the salt?

Are you sure you are reading the Salifert scale correctly? To check that, if you used most of a syringe to get to the color change, that’s high alk, not low. Many people read it backwards.

I am completely, utterly embarrassed. It was user error as you correctly surmised. The bucket is close to the tank and I absentmindedly used the tank water instead of the bucket water. In my feeble defense, I had not tested new water before today.

Hanna reads 9.9, Salifert 10.5 using water from the *bucket*. The difference is likely even less as I have a tough time determining the exact point to stop adding drops for the Salifert test- blue to dark purple to pink with a slight purple tint- the end latter is when I stopped adding.

I'm aware the tank water has low readings. Alk has been in a general, gradual decline over the last month and half-ish. That is why I decided to test the new water for alk today, to make sure it had the expected alk levels. I've also recently ordered the Alk booster kit from BRS. Having the newbie jitters about starting on dosing as that's a new thing to me and not confident if I understood the process very well yet.

Appreciate your and every one else's help. Now off to hide under a rock...

 

[Aaron75]

I am completely, utterly embarrassed. It was user error as you correctly surmised. The bucket is close to the tank and I absentmindedly used the tank water instead of the bucket water. In my feeble defense, I had not tested new water before today.

Hanna reads 9.9, Salifert 10.5 using water from the *bucket*. The difference is likely even less as I have a tough time determining the exact point to stop adding drops for the Salifert test- blue to dark purple to pink with a slight purple tint- the end latter is when I stopped adding.

I'm aware the tank water has low readings. Alk has been in a general, gradual decline over the last month and half-ish. That is why I decided to test the new water for alk today, to make sure it had the expected alk levels. I've also recently ordered the Alk booster kit from BRS. Having the newbie jitters about starting on dosing as that's a new thing to me and not confident if I understood the process very well yet.

Appreciate your and every one else's help. Now off to hide under a rock...

Glad you got your answer! No shame, stuff happens. Welcome to reefing. Lol