Tropic Marin High Precision Hydrometer

[RaymondL]

I am using one of them handheld refractometers that you hold up to the light to get the reading - it was recommended that I'd get a hydrometer as well to cross reference. I don't know if this is necessary a good idea as both instruments I think would report a different number anyways, and I'd be chasing a number that I don't know which is the real/most accurate one.

Curious what others here think - some I know swear by Milwaukee meters, but it's on the pricey end for me.

 

[ChiCity]

get the tm hydrometer.
worth every penny!
just gotta be careful with it since it’s delicate…

 

[Sean Clark]

The Tropic Marin High Precision Hydrometer is a great reference tool. The benefit of a Hydrometer is that it does not need to be calibrated. The reading should always be consistent over it's lifetime. The down sides are that they are fragile and you need a separate vessel to take your measurement in.

 

[RaymondL]

get the tm hydrometer.
worth every penny!
just gotta be careful with it since it’s delicate…

Thanks - based on your experience, is the Hydrometer very accurate?

 

[ChiCity]

Thanks - based on your experience, is the Hydrometer very accurate?

yes, extremely.
you never have to calibrate…

 

[RaymondL]

The Tropic Marin High Precision Hydrometer is a great reference tool. The benefit of a Hydrometer is that it does not need to be calibrated. The reading should always be consistent over it's lifetime. The down sides are that they are fragile and you need a separate vessel to take your measurement in.

Hmm, unless at the factory the hydrometer wasn't properly calibrated - it's a sealed unit, so the hope is that Tropic Marin has really nailed down the calibration process in such of their product.

 

[RaymondL]

yes, extremely.

Thanks - off to local LFS to pick one up. I'm going this route over digital - more cost effective for one.

 

[ChiCity]

grab yourself a 500ml (plastic) graduated cylinder too…
fill that with h20 and get your reading from in there

 

[tkong]

Just get the Milwaukee. Worth the money for convenience. Started with a refractometer and TM hydrometer. And recently got the Milwaukee. Wish I had just forked the money in the beginning.

 

[KStatefan]

500 ml graduated cylinder to measure in with 450 ml of tank water.

Make 450 ml of Randy's diy calibration solution 1.0264 Standard 17.3 grams Morton Table Salt and 450 ml RODI to verify the hydrometer.

Use a correction calculator if water is not at 77° F

 

[trevorhiller]

I don't have the Tropic Marin one, but I have a bunch of other common devices.

I really like my VeeGee STX 3 refractometer so far. I have way too many gadgets to check salinity and this one is the quickest and easiest to use. I use it is as my "master" reference. The milwaukee is my least favorite, it's not very accurate or precise and it's big and bulky.

I do like the Hanna pen now that I figured out how to make bulk reference solution for cheap and don't have to worry about buying calibration packets all the time.

The VeeGee tested closest to my ICP test I just did for what that's worth...

If you're interested, VeeGees are also on sale at Amazon right now for a good price.

 

[RaymondL]

I don't have the Tropic Marin one, but I have a bunch of other common devices.

I really like my VeeGee STX 3 refractometer so far. I have way too many gadgets to check salinity and this one is the quickest and easiest to use. I use it is as my "master" reference. The milwaukee is my least favorite, it's not very accurate or precise and it's big and bulky.

I do like the Hanna pen now that I figured out how to make bulk reference solution for cheap and don't have to worry about buying calibration packets all the time.

The VeeGee tested closest to my ICP test I just did for what that's worth...

If you're interested, VeeGees are also on sale at Amazon right now for a good price.

Thanks - I just checked the VeeGee STX 3 - it definitely surpasses the price point of the lower cost refractometers out there. I'm wondering if paying more for one will give any more accurate reading that another refractometer - do you have another refractometer of similiar to compare against, and if so, what were the results?

Thanks

 

[ChiCity]

refractometers are a step below hydrometers…

you will constantly have to recalibrate
vs
just dropping in a hydrometer and checking salinity

 

[trevorhiller]

Thanks - I just checked the VeeGee STX 3 - it definitely surpasses the price point of the lower cost refractometers out there. I'm wondering if paying more for one will give any more accurate reading that another refractometer - do you have another refractometer of similiar to compare against, and if so, what were the results?

Thanks

Yes it definitely is more quality. They are likely both accurate, but this will hold calibration much better IMO. I haven't had to adjust mine since buying it and I've heard of others having it for years without recalibrating.

It also is the only refractometer that I know of designed to calibrate w/RODI water rather than calibration solution which makes quickly calibrating before every use super convenient and easy.

The key with any of them is to calibrate it before every use (ideally). That's how you know it's giving you accurate results.

My cheap Amazon refractomer burned me once by coming off calibration by 2 points. Luckily it wasn't more, but I had just calibrated the time before. I don't use that one anymore - they are cheaply made in China and not for serious hobbyists IMO.

Salinity is probably the most important parameter as it effects everything in the tank, yet we recommend people use a $15 chinese device to test it. That seemed silly to me so the $77 for the VeeGee is well worth it.

 

[trevorhiller]

refractometers are a step below hydrometers…

you will constantly have to recalibrate
vs
just dropping in a hydrometer and checking salinity

This is true^. The benefit is durability.

 

[GuppyHJD]

grab yourself a 500ml (plastic) graduated cylinder too…
fill that with h20 and get your reading from in there

I have been turning off all pumps in the tank and just putting the hydrometer in the display tank - is there something I should be concerned about?

I looked into getting a cylinder but was not sure about it sticking to the walls and taking water out of the tank and the ATO filling back with RODI water?

 

[EricR]

I have been turning off all pumps in the tank and just putting the hydrometer in the display tank - is there something I should be concerned about?

I looked into getting a cylinder but was not sure about it sticking to the walls and taking water out of the tank and the ATO filling back with RODI water?

I have the Tropic Marin Precision Hydrometer and used it in the tank with flow off a few times but it's too much hassle since water in the tank keeps moving for quite a bit of time.

Switched to using 500 mL cylinder like others have mentioned and just turn off ATO while doing it.
*my devices are all plugged into a power strip with individual switches so turning off/on just the ATO is easy

EDIT -- the TM device is a big/heavy unit so friction against side walls of the cylinder is not a concern

 

[Alexraptor]

Crazily enough, I'm still using my old Coralife Deep Six swing-arm hydrometer, that I bought when I first started in this hobby, 18 years ago, and it still holds true!

Personally not sure I would trust myself with a glass one, on account of how many times I've dropped this thing to the floor.

 

[Hats_]

i use a refractometer generally for the ease of use, but i do have the TM high precision hydrometer as a backup, never failed me before and doesnt lose calibration. I have seen a trend back in the day with cheaper hydrometers in which the scalepaper moved up in the glass but havent seen that in the tm one

 

[Rst]

I also use the Tropic Marin Precision Hydrometer. I recently discovered the attached correction table for the Tropic Marin Hydrometer. It assumes that the hydrometer is calibrated at 25 degrees C. Does anyone know how to use this table? I think that the table gives a correction factor to apply to the reading?? For example, if the hydrometer reads 1.026 but my actual tank's temperature is at 24 degree C., how do I obtain the corrected salinity? Seems very confusing.

Thanks