Refractometer

[thall17]

What do you use for a refractometer? I bought the Milwaukee MA886 and just seems like an expensive tool when I can use the standard one that you hold up to the light....

 

[TastesLikeChicken]

The standard one that you hold up to the light. Tried and true.

 

[Fish Fan]

The standard one that you hold up to the light. Tried and true.

To be fair, a good floating glass bulb hydrometer with an appropriately sized graduated cylinder is perhaps the "gold standard", but these are just simply inconvenient for most of us keeping aquaria. You're right about a typical refractometer, I believe.

I have and LOVE the Milwaukee digital refractometer, I find it easy to use, read, and sanitize between tanks (<that last point is important to me). But, it's been pointed out that it's not the most accurate (hobby-level) *instrument*, so I no longer recommend it (but I still use it because it's so convenient lol!)

I recently purchased the Hanna HI98319 salinity checker, and I haven't yet used it, but this was a recommended choice, so I have high hopes.

I'd be interested in hearing any other options :)

 

[Gtinnel]

I have the old school optical refractometer, a Hanna salinity pen, but the one that I always use is my Milwaukee digital refractometer. It’s nice to have IMO, but definitely not a necessity.

Also, I’m not sure if you actually have the MA886 but the one used for measuring salinity is normally the MA887.

 

[BeanAnimal]

I have thrown two Milwaukee digital refractometers in the trash. IMHO, junk.

I use the TM floating hydrometer as a reference standard and two refractometers to match it. When/if the refractometers don’t read the same, I reset them to match the TM. Maybe once a year they need to be adjusted.

I use the refractometers mainly as a sanity check for the GHL conductivity probe.

 

[TastesLikeChicken]

So it seems that the consensus is that the TM floating hydrometer is the most accurate device. Is this correct?

 

[BeanAnimal]

So it seems that the consensus is that the TM floating hydrometer is the most accurate device. Is this correct?

Yes - each device is factory calibrated. There are no moving parts.

 

[edsbeaker]

I use the TM hydrometer. It is large, it is fragile, but when I use it I know I will always get consistent results each and every day without the need to calibrate.

 

[Randy Holmes-Farley]

So it seems that the consensus is that the TM floating hydrometer is the most accurate device. Is this correct?

It may be the cheapest device with good accuracy and nearly foolproof use. It is not the most accurate, which is likely a high end conductivity meter. Just keeping the perspective on the strong word “most”. Chemical oceanographers use conductivity meters, and that is how the PSU salinity scale is defined.

 

[BeanAnimal]

It may be the cheapest device with good accuracy and nearly foolproof use. It is not the most accurate, which is likely a high end conductivity meter. Just keeping the perspective on the strong word “most”. Chemical oceanographers use conductivity meters, and that is how the PSU salinity scale is defined.

I would not disagree with this. My fault for accepting most, as in the context of the devices discussed in this thread.

I do wonder though how accurate and precise a reference meter is compared to the TM. It would be interesting to see a controlled test, even if it is pointless for our purposes.

 

[TastesLikeChicken]

Is it the most accurate device for the home aquarist? (That would be me ).

 

[Randy Holmes-Farley]

Is it the most accurate device for the home aquarist? (That would be me ).

No, but it is plenty accurate enough (I would validate its performance at least once since it could be made incorrectly). It has drawbacks though, being inconvenient and folks need to be aware of temperature effects.

Plenty of home hobbyists use high quality conductivity meters. They cost substantially more, but are more convenient and have more uses, such as during acclimation or potency of kalkwasser.

 

[Randy Holmes-Farley]

I would not disagree with this. My fault for accepting most, as in the context of the devices discussed in this thread.

I do wonder though how accurate and precise a reference meter is compared to the TM. It would be interesting to see a controlled test, even if it is pointless for our purposes.

I think the limitations of either one, but especially the hydrometer cannot be readily tested in a single device. In the hydrometer case, for example, two likely issues are how precise and correctly can an individual read it, but also how accurately it is marked. The latter would need a bunch of devices to test that aspect.m to make generalizations. Sounds like a lot of work. lol

 

[DOJOLOACH]

I'm giving the TM hydrometer a try. It was that or the 250 hanna which I just can't justify $$$