Hanna alk checker

[Perthegallon]

Hello guys so I just bought a Hanna alk checker and even despite using Red Sea black bucket of salt mixed at 35 (checked with two calibrated instruments)

I keep getting a Hanna checker reading 7.2-7.8

Why is my Hanna this inaccurate

I even tried a precision 10 mm syringe I have, and it’s still will not fix it

 

[Perthegallon]

The dkh at least not from the tank but the fresh bucket I mixed should be 12 dkh

 

[gbroadbridge]

Hello guys so I just bought a Hanna alk checker and even despite using Red Sea black bucket of salt mixed at 35 (checked with two calibrated instruments)

I keep getting a Hanna checker reading 7.2-7.8

Why is my Hanna this inaccurate

I even tried a precision 10 mm syringe I have, and it’s still will not fix it

Have you checked with another Alk test like Salifert?

The Hanna Alk is usually within about +- 0.5 dKh with fresh reagent

 

[Perthegallon]

Have you checked with another Alk test like Salifert?

The Hanna Alk is usually within about +- 0.5 dKh with fresh reagent

Reagent is fresh. I have a salfert kit and is showing the correct numbers

 

[ReefStable]

If the other test looks good, you may need to contact Hanna. The calibration may be bad.

 

[gbroadbridge]

Reagent is fresh. I have a salfert kit and is showing the correct numbers

By fresh you mean unopened Hanna reagent and before expiry right?.

What Alk is the salifert test showing?

How did you calibrate your salinity measurement device?

 

[Perthegallon]

By fresh you mean unopened Hanna reagent and before expiry right?.

What Alk is the salifert test showing?

How did you calibrate your salinity measurement device?

Yes to both.

You know now I check with the salfert kit I’m getting the same results in my fresh bucket of salt water mixed as well as tank 7.8 dkh and 7.4

I don’t know how this would be being that I’m using black bucket Red Sea salt

For salinity I can see my calibrated apex prob showing close to 35
I’m also using just calibrated today Hanna hand held salinity checkers
I also have two salinity optics reflectors one of them is the really nice 300$ one and the other a 40$ one and I have a calibration solution from saltwater Aquariam and brs

 

[Perthegallon]

So I’m unsure what I’m doing wrong here

 

[Perthegallon]

#reefsquad

 

[ReefStable]

I honestly think you may have just gotten a bad hanna checker. I would just contact Hanna (or the store you bought from) for a replacement.

It doesn't happen often, but every once in a while it can happen.

 

[Perthegallon]

I honestly think you may have just gotten a bad hanna checker. I would just contact Hanna (or the store you bought from) for a replacement.

It doesn't happen often, but every once in a while it can happen.

But it’s very accurate with the salfert kit so I’m now surprised

 

[Gribbles]

Sounds like your bucket isn't mixing up to expectations. Can you take a sample of tank water and also newly-mixed water to your LFS and have them double check?

 

[Perthegallon]

Sounds like your bucket isn't mixing up to expectations. Can you take a sample of tank water and also newly-mixed water to your LFS and have them double check?

Hm this is a new bucket to which is weird because I don’t think both would be off two different purchases spanning like 5 months

 

[gbroadbridge]

Yes to both.

You know now I check with the salfert kit I’m getting the same results in my fresh bucket of salt water mixed as well as tank 7.8 dkh and 7.4

I don’t know how this would be being that I’m using black bucket Red Sea salt

For salinity I can see my calibrated apex prob showing close to 35
I’m also using just calibrated today Hanna hand held salinity checkers
I also have two salinity optics reflectors one of them is the really nice 300$ one and the other a 40$ one and I have a calibration solution from saltwater Aquariam and brs

Okay, so I think you're saying that the Salifert and Hanna roughly agree with each other.

If your freshly mixed saltwater bucket is measuring low Alk, try measuring Calcium and see if that is low.
If so that would indicate your salinity is also low.

If Ca is close to what you expect it could be a bad batch of salt although I think that very unlikely.

Are you following the mixing instructions supplied by Red Sea and only heating after the salt has dissolved and pH has stabilised.

ed: It's quite important to not mix for too long - it should be used as soon as dissolved and pH has stabilised.

 

[MrGisonni]

Is the seawater batch really mixed completely and clear??

 

[SPR1968]

I would say it’s more likely the saltwater is mixing to what the Hanna / salifert says or thereabouts, but then again it wouldn’t take much to produce a low reading depending on mix etc.

Oh and I certainly would not use the Apex salinity probe as a judge of actual salinity from my own experience with it. Get a salinity device that you can trust, like Hanna, Red Sea refractometer etc.(I see you have), and then use that and then calibrate Apex to that. Otherwise it could be way out.

 

[Uncle99]

Mine was never accurate.
Sits in the box now.

 

[ryanjohn1]

Did you mix the dry salt mix prior to adding to water? I usually roll buckets or bags around a bit. On a side note. This is why I switched to nyos salt. I was using Red Sea black bucket for years and the last year of it batch’s were really inconsistent

 

[nereefpat]

As long as you are performing the Salifert test correctly (The difference between where the plunger begins and ends is the amount of titrant added), I put all my trust in that test. Alkalinity is a titration by definition, and the Salifert is a titration that is +/- about 0.3 dKH.

I'm not sure why the Hanna may give strange readings. If it matches the Salifert, and you like using it, then great. You could use it as your standard test, then check with the Salifert if you get an unexpected reading.

As for a salt mixing up to an unexpected Alkalinity reading, there could be a few reasons:
It is possible to get a bad batch, but that's pretty unlikely.
I know BRS did a test on buckets of salt being mixed. Whatever their results, the individual components can separate. It's actually pretty amazing to me that a factory can get all that stuff in there somewhat evenly.
Or, as mentioned, make sure your salinity measuring device is calibrated. My opinion is that the best way to do that is by making your own standard with table salt and RODI and adjusting a refractometer to match. If you take a quart jar, put it on a kitchen scale that reads in 0.1 gram increments, zero it out, then add 36.5 grams of table salt by weight, then add 963.5 grams of RODI by weight, then shake it up, you have a full proof seawater standard.
The other way is by messing up the Salifert test somehow.

 

[Perthegallon]

So I’d like to update everyone and say I figured it out.
The Red Sea black bucket I bought had a alk of 7.2

I have no clue how it is so low and it’s crazy that this made it through Red Sea I’m lucky I actually used 90% of the bucket on a new tank I’ve recently set up and not one of my established ones