Alexander1312
Supporting Member
Has anyone come across this product or seen something similar from another brand?
Hydrometer + built-in thermometer
- Thread starter Alexander1312
- Start date
psidriven
Supporting Member
some of the cheap hydrometers also are thermometers. my main criteria is how big is the salinity measurement scale. i have a hard time telling what is the SG when the 1.020-1.030 is a centimeter long.
ibspot.com
Fish Tank Aquarium Glass Float Hydrometer w/ Thermometer Salt Water Marine 20 cm
For aquarium Floating type Easy accurate readings Ideal level between 1.020-1.025
ibspot.com
Alexander1312
Supporting Member
I had to go to a French site to purchase this (since they were the only ones in Europe that ship worldwide) - https://www.recifart.com/en/water-t...P4*MTc0MDk4NDAxNS4xLjEuMTc0MDk4NDA2Ny4wLjAuMA..
This hydrometer is considered the only one slightly better than the All-Star Tropic Marin hydrometer. Not sure if this is correct but I thought the TM has the lack of temp reference as its main drawback. Maybe not a big deal. I also like that this one comes with a see-through cylinder made for it. All are just minor features, further improving on the fact that hydrometer in general are a better way to measure the most important water parameter, i.e., salinity.
Also, I am getting tired of the Milwaukee refractometer because the last results of been unstable and the latest ICP showed 35.7 PSU while I measured salinity on the same day at 35 - I know @dandemeyere made a comment that his fell out of calibration after some time and it seems as if mine is doing the same. Time for change.
This hydrometer is considered the only one slightly better than the All-Star Tropic Marin hydrometer. Not sure if this is correct but I thought the TM has the lack of temp reference as its main drawback. Maybe not a big deal. I also like that this one comes with a see-through cylinder made for it. All are just minor features, further improving on the fact that hydrometer in general are a better way to measure the most important water parameter, i.e., salinity.
Also, I am getting tired of the Milwaukee refractometer because the last results of been unstable and the latest ICP showed 35.7 PSU while I measured salinity on the same day at 35 - I know @dandemeyere made a comment that his fell out of calibration after some time and it seems as if mine is doing the same. Time for change.
Alexander1312
Supporting Member
Speaking of user errors, @derek_SR.
So I bought the above hydrometer some time ago, but only used it once briefly (everybody knows it is a very fragile piece of equipment).
My ICP came back today and salinity is still at 35.7 PSU, despite using the Milwaukee refractometer differently - I am waiting now longer until I accept the reading.
In my parameter recordings, it looks as if the Milwaukee also measured a higher salinity at the time I took the ICP so maybe this is now ok.
Still, I want to start using the Hydrometer now for greater precision.
My question is now (I will elaborate later why I ask this here): How much is 1.0237sg (77F) in PSU?
So I bought the above hydrometer some time ago, but only used it once briefly (everybody knows it is a very fragile piece of equipment).
My ICP came back today and salinity is still at 35.7 PSU, despite using the Milwaukee refractometer differently - I am waiting now longer until I accept the reading.
In my parameter recordings, it looks as if the Milwaukee also measured a higher salinity at the time I took the ICP so maybe this is now ok.
Still, I want to start using the Hydrometer now for greater precision.
My question is now (I will elaborate later why I ask this here): How much is 1.0237sg (77F) in PSU?
Salinity calculator
A unit converter for calculating salinity in marine aquariums. The calculator supports conductivity (mS/cm), salinity (PSU og ppt), density (g/cm³) og specific gravity.
reefapp.net
RandyC
Supporting Member
I don't understand why you're fretting about 0.7 PSU or what your end game is trying to be so precise. But at any rate, that's within the device's error range, so it's functioning as normal. If you want something more accurate, the Milwaukee MA887 is not your answer.
From Milwaukee MA887 manual.
Last edited:
Alexander1312
Supporting Member
Salinity calculator
A unit converter for calculating salinity in marine aquariums. The calculator supports conductivity (mS/cm), salinity (PSU og ppt), density (g/cm³) og specific gravity.
View attachment 68412
View attachment 68411
Thanks so much. The link was particularly helpful. While I knew this was indeed a user error, I could not find the issue. I have only used a refractometer in the past, and really mostly the Milwaukee. And I only targeted PPT or PSU.
Looks like I thought the measurements from the Hydrometer result in specific gravity values, while they are in fact density values.
This confirms then my issue that my salinity is slightly elevated (need to double check the temperature reading).
Should have gotten the Tropic Marin hydrometer
Alexander1312
Supporting Member
Should have gotten the Tropic Marin hydrometer
And another helpful comment from you, thank you. I thought I misunderstood the way Hydrometer operates but as you said, the Tropic Marin Hydrometer measures specific gravity vs density so I am glad I do not feel as ‘uninformed’ aka stupid anymore….
Last edited:
I recently got mine and I love it. I wish it included a guide on it with ppt, but the online conversion app is amazing. I've used it to calibrate my digital probes also for quick readings.Should have gotten the Tropic Marin hydrometer
@Alexander1312 What's your target ppt? I've had stuck in my head since I came here, something @IOnceWasLegend told me. Keep your range between 33-35ppt and you'll be ok. So I stuck with that and went with 34 as a goal. Gives me wiggle room on each side. I recently found a couple tanks went high on me too. So it was nice to get the hydrometer to make comparison reads and adjust accordingly.
Alexander1312
Supporting Member
You know, I am a Fauna Marin fanboy, and they are all into 35 PSU as the target parameter, and base their dosing recommendation on this.
Also, this is a copy from my favorite Reef Chemistry book (German only), which shows the salinity ranges of the various oceans. My conclusions from this was that 35 PSU seemed more appropriate.
I like it! It's a good target IMO. Nothing wrong with seeking precision in your husbandry. I respect it.
Big fan of the TM hydrometer. With the recommendation that it should be measured at 25C/77 F -I generally test it as soon as I pull water from the tank as I keep my temp at 77. And I have two probes giving me nearly same temp so “good enough” and if the sg is between the blue lines -“good enough”.