Hanna Hl98319 salinity tester.

[DeniableArc]

How often are you calibrating your Hanna salinity tester? I ask because about 6 months ago I ungraded from a good quality refractometer to Tyne Hanna electronic salinity tester for a greater accuracy. I understand that the device has a +/- 1 ppt accuracy but I feel the need to calibrate at least every 3-4 weeks with a use of 4-8 times a month. My aquarium has a flawless ato and I feel it maintains a stable salinity and when I do my 10% weekly water change in the same bucket using the same measured amount of salt, but even with all my consistency the Hanna is definitely no more accurate then the +/-1 ppt. Should I not worry about this reasonably small variation or invest in a better salinity tester?

 

[Doctorgori]

I have been burned trusting electronics with my fish. digital pH. and digital thermometers are notoriously inconsistent. every now and then I still checksum my Hanna salinity with my refractometer

 

[Randy Holmes-Farley]

How are you calibrating it?

I voted never because my conductivity meter (Orion model 128) cannot be "calibrated". it can be checked against a standard, but not actually calibrated.

For any device, calibrate it as often as it seems to need it (that is, as long as it takes for it to drift off your acceptable accuracy), or when a reading is unusual and you are about to act on it.

 

[NeonRabbit221B]

Checking salinity is slightly redundant to me. I check salinity about every other week when I do WC and testing. Choose monthly but in reality is about every two months or whenever I am questioning the results or want a precise reading.

 

[Adamantium]

After going almost 3 months without calibrating, and finding out my reading was about 3 PPT lower than actual, I now make a point to calibrate monthly.

 

[DeniableArc]

How are you calibrating it?

I voted never because my conductivity meter (Orion model 128) cannot be "calibrated". it can be checked against a standard, but not actually calibrated.

For any device, calibrate it as often as it seems to need it (that is, as long as it takes for it to drift off your acceptable accuracy), or when a reading is unusual and you are about to act on it.

Thanks for the reply. I am using the Hanna Hl98319 35ppt solution made for that particular checker. As far as how often I calibrate, it seems very consistent 90% of the time but it’s a slow drift when I think it’s out I recalibrate it and it might be 0.5-1ppt out and me being ocd I feel the need to correct the salinity in my display asap. So I guess in a nutshell is a 1ppt salinity swing over say 1 hour a big problem?

 

[Adamantium]

Thanks for the reply. I am using the Hanna Hl98319 35ppt solution made for that particular checker. As far as how often I calibrate, it seems very consistent 90% of the time but it’s a slow drift when I think it’s out I recalibrate it and it might be 0.5-1ppt out and me being ocd I feel the need to correct the salinity in my display asap. So I guess in a nutshell is a 1ppt salinity swing over say 1 hour a big problem?

What do you mean when you say "over 1 hour"? Do you mean month?

 

[DeniableArc]

What do you mean when you say "over 1 hour"? Do you mean month?

If I recalibrate the meter and my display is over 35ppt I take water out over an 30min to an hour and let ato replenish if it’s under I mix up stronger 10% water change 1 or 2 times.

 

[Randy Holmes-Farley]

Thanks for the reply. I am using the Hanna Hl98319 35ppt solution made for that particular checker. As far as how often I calibrate, it seems very consistent 90% of the time but it’s a slow drift when I think it’s out I recalibrate it and it might be 0.5-1ppt out and me being ocd I feel the need to correct the salinity in my display asap. So I guess in a nutshell is a 1ppt salinity swing over say 1 hour a big problem?

IMO, on the device, if the calibration drifts around +/- 1 ppt, I'm not too concerned. if it continually drifts one direction, I'm concerned.

 

[Randy Holmes-Farley]

If I recalibrate the meter and my display is over 35ppt I take water out over an 30min to an hour and let ato replenish if it’s under I mix up stronger 10% water change 1 or 2 times.

I would not make a 1 ppt change in 1 h.

 

[Adamantium]

If I recalibrate the meter and my display is over 35ppt I take water out over an 30min to an hour and let ato replenish if it’s under I mix up stronger 10% water change 1 or 2 times.

Oh, I understand now. That's never been an issue for me.

 

[Adamantium]

IMO, on the device, if the calibration drifts around +/- 1 ppt, I'm not too concerned. if it continually drifts one direction, I'm concerned.

That’s been my experience, actually. Once it starts drifting, it keeps going the same direction. I was reading 35PPT, but after recalibration I was actually all the way up to 38PPT.

 

[Adamantium]

I would not make a 1 ppt change in 1 h.

Really? I’m surprised to hear that. Changing salinity by .0008 SG in an hour is detrimental?

 

[Randy Holmes-Farley]

Really? I’m surprised to hear that. Changing salinity by .0008 SG in an hour is detrimental?

I'm not sure, but there's no reason to do it fast. 36 ppt steady is, IMO, at least as fine as a 1 h drop to 35 ppt.

On a decent size tank it is pretty hard anyway. You would need to replace 3% of the water with fresh water to drop salinity by 1 ppt. Why not replace a small amount a day for a few days? Or just do your regular water changes with salinity a bit low?

 

[Randy Holmes-Farley]

That’s been my experience, actually. Once it starts drifting, it keeps going the same direction. I was reading 35PPT, but after recalibration I was actually all the way up to 38PPT.

OK, that is a concern and I'd calibrate it reasonably often.

It's not an inherent attribute of the method. My Orion 128 never drifted more than +/- 1 mS/cm over more than 10 years.

 

[jopo4343]

I found this to work great for about a month. I calibrated it many many times since and it never stays true just drifts and test same water in 2 mins different reading. I classify this as junk.
contacted Hanna and got no response.

 

[Randy Holmes-Farley]

I found this to work great for about a month. I calibrated it many many times since and it never stays true just drifts and test same water in 2 mins different reading. I classify this as junk.
contacted Hanna and got no response.

Are you waiting long enough for it come to temperature?

All such meters will change values until it comes to temperature with the water. 2 minutes is not long enough with some (like the Pinpoint I used), so of course it will change during that time.

One of the reasons I liked my Orion 128 with 4 electrode probe is it came to temp faster to get a stable reading faster.

 

[homer1475]

I've honestly only ever calibrated my 3 times in 2 years, and twice was because I hit the "calibration" side of the button instead of the "off" part of the button.

With that said, I will "check" it from time to time with the calibration packets. If it reads 35ppt from the packet, no need to calibrate. Mine has been rock solid, and has only needed calibration on eht initial setup.

These salinity checkers seem to be hit or miss. You either get a good one, and it's good for a long while, or you get a dud that needs constant calibration.

 

[mike550]

Hanna suggests every 30 days, and I try to follow that. I make NSW weekly so that’s around 3-5 readings each time and then I measure my tank salinity a couple of times a week. So Im probably doing 25-ish readings each month.

 

[Adamantium]

I had a weird situation with mine recently. It was reading like 3 PPT too low, consistently, even with calibration. Then I accidentally pressed CAL, and it corrected itself haha

No idea what happened, but it seems to be accurate again.