Refractometer vs. Hydrometer

[Mostly Rock]

I have an Instant Ocean Hydrometer, it cost me 8 bucks and Ive tested it with a refractometer at 3 different LFS's. It has served me well for over a year. I used it all the time while I was transitioning my flounders from fresh, through brackish to marine. I insisted, no matter the argument, that my hydrometer was just as accurate as any refractometer. Today, my wife sent a txt to me while I was at work... My Green Star Polyp and my Prized RBTA were all shriveled and very sad looking. Helpless, I had her rush a water sample to the LFS and bring a few jugs in case an emergency water change was in order (yeah, my bad again, I didn't have any made up.) It turns out, my salinity was 1.030. My hydrometer insists it's 1.026. You were right, I was wrong. I'm ordering a refractometer today.

[Mostly Rock]

Does anybody have any experience with this one? http://www.ecrater.com/p/5141693/sal...ium-ocean-reef

[Amphibious]

Not familiar with that one. At $24 it’s either the best deal on a hydrometer or a piece of Chinese crap. Not at all sure. One statement they claim, “This is the most POPULAR Salinity Refractometer around! We've sold more than 10,000!”, I would highly doubt and therefore have doubts about the piece of equipment and the people making that statement. Anyone can make a statement, only truthful people can back it up with fact.

I’m not saying don’t buy it. At that price it is worth a try.

Dick

[V]

Anyone can make a statement, only truthful people can back it up with fact.

Ive got the biggest pecker in the world...... see...classic example right there!~ muhahaha

[SaltyDawg]

You need help. Good to see you around....I think..lol

[Mostly Rock]

Please don't try to back that one up

[CarmieJo]

A refractometer, when properly used and rinsed clean every time it is used, may be inaccurate but should be consistent. I am going to guess if it was consistently reading the same thing as the LFS refractometer that it was not rinsed clean or that it was otherwise damaged.

[Mostly Rock]

I did a search on that model (RHS-10ATC), and people on other forums gave it good reviews. I figure it's worth a try. I make a lot of stupid mistakes, buying cheap... Take my lights for instance... But my skimmer turned out well. I just need a bigger one now.

[Mostly Rock]

Crap... I think I just instigated a V comment...

[Mostly Rock]

Sorry Carmie, I missed your comment. I meant I was using a Hydrometer and I checked it with refractometers @ three LFS's a year or two ago... I always clean it before and after each use. I doubt it was a gradual shift, because the Anemone and the Green Star Polyp started acting funny within hours of a waterchange (my wife informed me of it when the lights came on, but I was at work) I got home and double checked everything and she was right, I dumped 1.030 specific gravity water into my display... actually, probably greater than that because the water in my DT was at 1.030 with a refractometer. My new refractometer will also be cleaned obsessivly, but I think the unit, by design, will be with me for a much longer time than the hydrometer was.

[CarmieJo]

You might want to make up some salinity standards to check the calibration. http://www.reefkeeping.com/issues/2004-06/rhf/index.php

[Mostly Rock]

I just got my refractometer! It's 1:45 am and the thing is frozen, in the morning... I mean the one that I will be involved in when I wake up in a few hours... I'll try it out. I'll keep everybody updated. A 27 dollar refractometer seems too good to be true. It looks solidly built, but I am pretty tired.

[rayme07]

Awesome I cant wait to hear the results, I hope it works correctly.

[Mostly Rock]

So far so good. I tested some RO/DI water and it read absolute zero, my mixed up water reads 1.020 and my tank reads 1.025. I'm gonna swing by the LFS to check it with their equipment and see if they have any calibration liquid. If it's accurate, I need to add some salt to my mix before my water change. At this point I feel like I got a great deal and I'm more confident in my readings.

[Mostly Rock]

OK, I've been using this for 5 days now? Comparing this unit with the refractometers @ a couple LFS's on day 1 was a success. Handling and cleaning it every day has given me a chance to inspect it for defects in workmanship, and it's not flawless, but it's just as well built as the 60 dollar unit at the LFS. I'm kinda obsessive about details, so finding flaws in things for me is like breathing. In all, I feel like it was a sound investment, and I recommend it to anyone who doesn't have a refractometer yet.

[CarmieJo]

That is good to hear!

[V]

Crap... I think I just instigated a V comment...

Dont do that, you'll get banned..lol

Just remember on refracto's, its the guide pins that get hit first, so protect them.

[Mostly Rock]

OK, maybe I'm too lazy to do a search on that tonight, so I'll have to express my ignorance publicly... Guide Pins? No Intendio. Now, I have already lost the cap that goes over the adjustment screw (Yeah, I walked into the room and found my 2 year old ON my desk, playing with "Daddy's new toy"...) and I had to re-calibrate it. It's fine though, no harm except for the loss of a small (Latex?) cap.

[CarmieJo]

You know two year olds generally climb like little monkeys. My mom will tell you the story about turning her back for a second when I was 2 and my sister 6 months old and seeing me climbing up the TV antenna tower at about the level of the roof!

I think that V means the little pins the top hinges on. I put Vaseline on mine.

[Mostly Rock]

Gotcha, I will do that Thanks!

[Mostly Rock]

Update. So far, my only complaint would be that I had to re-calibrate it once a week. I say had, because I haven't had to in the last two weeks. I don't know why. Maybe there's a break in period? Maybe it was getting bumped around a lot while I wasn't there? I dunno... But if you think about it, dropping some RO/DI water on it and tweaking it with a tiny screwdriver once a week isn't a huge deal compared to the money I saved. All said and done, I feel like I scored on this one.

[CarmieJo]

I've only had to recalibrate mine a couple times.