Throw away Plastic hydrometers !

[AdamB]

Okay, I have been using a instant ocean plastic hydrometer for a couple years now and never pulled the trigger on salinity refractometer until I bought another instant ocean and a accuprobe hydrometer since to replace and come up find out all 3 hydrometers are way off! My old hydrometer reads a little over 1.024 while the other 2 reads 1.030 and other way past 1.032!
I am hoping that my first hydrometer I’ve Been using for past couple years is accurate since my coral have done okay? Luckily ,a guy that a bought lot of coral from last week gave me a new refractometer and I am just waiting from the calibration fluid to arrive in Mail tomorrow!
So I am really upset to know that the plastic hydrometers can be so far off!
My fault though , I should have bought a refractometer long time ago!

 

[hotdrop]

honestly all these tools will have problems if you don’t calibrate them. As long as you have a reference standard all of em work fine

 

[ScottB]

I gave up on those pretty quick. If you rinse in RO after each use, inspect closely for ANY small bubbles on the arm then I found they can just keep you out of trouble. Most of the time.

Refractometers do need to be recalibrated and kept reasonably clean.

 

[Dr. Dendrostein]

Okay, I have been using a instant ocean plastic hydrometer for a couple years now and never pulled the trigger on salinity refractometer until I bought another instant ocean and a accuprobe hydrometer since to replace and come up find out all 3 hydrometers are way off! My old hydrometer reads a little over 1.024 while the other 2 reads 1.030 and other way past 1.032!
I am hoping that my first hydrometer I’ve Been using for past couple years is accurate since my coral have done okay? Luckily ,a guy that a bought lot of coral from last week gave me a new refractometer and I am just waiting from the calibration fluid to arrive in Mail tomorrow!
So I am really upset to know that the plastic hydrometers can be so far off!
My fault though , I should have bought a refractometer long time ago!

Ooooooo boy, don't tell @Paul B that. He actually goes island to island and checks calibration on his. He sends photos once in a while doing calibration there....Hahaha

Between us, I think he's old school, shhhhhhhh between us.

 

[Dine]

Consistency is way more important then hitting an exact number. That’s why your corals have been fine. If you see the new measurement is off from where you want to be bring it up or down SLOWLY

 

[brandon429]

ill never own a refract as long as I reef. right now I can search up 20 wrongly calibrated refract read threads. my swingarm is so old it has hardly any numbers on it. once a decade I check it against a lfs refract, it reads high but consistent any year checked. when I see .024 on my swingarm I know the water is really .025 etc.

Ill be able to keep any coral we want to keep w that or any other swingarm, if there's two things im principally against in reefing its ammonia testing and refractometers lol.

 

[hotdrop]

ill never own a refract as long as I reef. right now I can search up 20 wrongly calibrated refract read threads. my swingarm is so old it has hardly any numbers on it. once a decade I check it against a lfs refract, it reads high but consistent any year checked. when I see .024 on my swingarm I know the water is really .025 etc.

Ill be able to keep any coral we want to keep w that or any other swingarm, if there's two things im principally against in reefing its ammonia testing and refractometers lol.

I was actually thinking of switching to a swing arm if I can find a good quality one. Refractometer reading is way too sensitive to temperature and lighting. With a good reference standard there really shouldn’t be any issues.

 

[brandon429]

Ive literally never owned a bad one. I cannot figure out how they get such a bad rap, aware refracts are laser accurate when working perfectly. I see them as a need only at water change time. the classic magic marker reference dot/evaporation replaced back up to that level is the ultimate in accuracy for my salinity, its only at water change time I need the goods

I could walk into petsmart right now, select first avail swingarm, and reef with it uncalibrated the next ten years. it wont read exactly as mine does now, but whatever the range tank will adapt to instantly cuz that's how this last refract came into use. the one before it was totally clear of all ink so I bought one more. been reefing twenty years have owned two swingarms only

 

[CasaReefer]

Just break down and buy the Milwaukee MA887.. Just AWESOME......

 

[EMeyer]

Lots of reasons to favor one salinity instrument or another. But it's hard to argue against conductivity as the best resolution. All instruments need to have their calibration checked routinely, but some instruments aren't easy or possible to calibrate if they're off.

Appropriately calibrated, all can be accurate. Precision is good enough IMO for all of them, as long as the user measures it at least twice and takes the average.

Swing arm is at the bottom of my list, and haven't used one in years. Low resolution and not readily calibrated

 

[brandon429]

someone once said in a thread they wont use a swingarm due to basket stars and linkia/very sensitive animals that need exacting no drifts for makeup water. I would agree fail to thump some bubbles can make a swingarm off a bit, we just get lucky that all the corals we like tolerate that variance like a rainy day on the reef etc. more sensitive animals surely might not

 

[Braves Fan]

I use one of the plastic ones ,, took a water sample into the LFS the other day ,, I had tested the water before I took it in ,, tested at 1.76 he tested it ,, was 1.29

 

[X-37B]

Dont throw away you IO swingarm.
I have a refrac and calibrate it before each use/ reading. My IO reads 1.027 when my refrac reads 1.026. The IO is quick and easy and is a good backup. Just make sure no bubbles are on the arm. Even small micro bubbles will alter the reading. Rinse it in di and dry. The IO if used and cleaned properly will give repeatable readings. You just need to know the difference in the actual reading and your good to go. Not much that can go wrong with IO unless you dont clean it properly.

 

[brandon429]

I have a song and dance that makes mine trustworthy, excellent call. swingarm old schoolers do not fill and read that's right, my steps are thump/wait / thump lol then read. then right foot in/left foot out

 

[Braves Fan]

I wont throw mine away ,, I will just test to 1.25 ,,, should be at 1.27

 

[RmSchuh]

Classic hydrometer works but there is a calibration for them. Most people don’t know that at the end of the day I like to be precise on my salinity. Doing auto water change I keep my salinity at 1.026 and it will stay constantly 1.026 precisely. Keep to successful reef tank is accuracy and stability. Just invest in the almighty Milwaukee digital refractometer

 

[AdamB]

I gave up on those pretty quick. If you rinse in RO after each use, inspect closely for ANY small bubbles on the arm then I found they can just keep you out of trouble. Most of the time.

Refractometers do need to be recalibrated and kept reasonably clean.

Yes , I am giving up on them as well even though my tank has survived well.
I can live with recalibration on refractometers .

 

[AdamB]

Classic hydrometer works but there is a calibration for them. Most people don’t know that at the end of the day I like to be precise on my salinity. Doing auto water change I keep my salinity at 1.026 and it will stay constantly 1.026 precisely. Keep to successful reef tank is accuracy and stability. Just invest in the almighty Milwaukee digital refractometer

I will look into that refractometer. This is one piece of reef inventory I have not paid much attention to until now! Thanks!

 

[TheOne]

You should get in the habit of calibrating a refractometer on a regular basis. I calibrate mine to the same temp also.

 

[AdamB]

Consistency is way more important then hitting an exact number. That’s why your corals have been fine. If you see the new measurement is off from where you want to be bring it up or down SLOWLY

Yes . I know that is the truth! I have been battling 0 nitrates and phosphates last month and that was so aggravating!