Refractometers!?!?!?

[mike007]

Hi all, i have been in the market for a refractometer and i found a couple different types that i would like.

Saltwater Aquarium Salinity & Specific Gravity Testing: Portable Refractometer

Sybon Refractometer with Automatic Temperature Compensation | Refractometers | Testing Equipment | Aquarium - ThatPetPlace.com

C-Scope Refractometer | Refractometers | Testing Equipment | Aquarium - ThatPetPlace.com

does anyone have one of these that they would recommend? i currently have a 90 gallon FOWLR tank and im still setting it up. its going to become a reef tank soon but i want to have all the equipment necessary b4 i get into that. any advice for other equipment that would be helpful for the change would be greatly appreciated!! thanks all

[zhenya]

Hi mike007,




I've been usin Cybon refractometer since 05 without any problems. I think I paid like $80 at the time for mine, so $41 is agreat price for it. You won't be disappointed with it.

PS. In case you missed this, we discussed refractometers in this thread

[mike007]

i was leaning towards the Cybon. ok thanks Gene

PS. thanks 4 the welcome

[Ninong]

Hi mike007,




All of those refractometers would probably do the job. The prices are very close. I would probably go with either the first one or the last one and skip the cheapest one. I guess I didn't spend enough time reading the difference between the second one and the third one because I think they're both sold by the same people. Just go with the third one and be done with it.

I found this advice on there:

Accurate measurement depends on careful calibration with distilled water. The prism and sample must be at the same temperature for accurate results. Do not expose the instrument to damp working conditions, and do not immerse the instrument in water. If the instrument becomes foggy, water has entered the body, and the instrument should be replaced.

Then they tell you that they sell 53 mS calibration fluid. Okay, if you buy the 53 mS calibration fluid, then you won't be using distilled water for calibration. Zhenya did this and he likes it that way. That's certainly a good way to go. Unnecessary, IMO, but good nonetheless.

You use the calibration fluid to re-calibrate your refractometer so that 35 ppt on the scale matches the 53 mS calibration fluid. After you do that, distilled water will no longer read 1.000, so you can't used distilled water to calibrate it. Unless you run out of 53 mS calibration fluid and decide to re-calibrate it back to where distilled water equals zero.

This is entirely too complicated to explain in this thread because I already typed pages about it in that other thread that zhenya linked. I just hope that reading that thread doesn't confuse you.

Summary: Buy a refractometer! You will love it. They're cheap (less than $50) and very, very nice.

You can go either with or without the 53 mS calibration fluid. You will have to read that entire thread to understand what we're talking about. I just hope it doesn't give you a headache.

[Ninong]

Gene,

What are you guys talking about, Cybon? Do you mean Sybon? The middle one?

Oh, well. At least I said that all three of them would probably do the job. I was just eliminating the cheapest one.

[mike007]

Hi mike007,

is this like the dunce hat for new users? LMAO


thank you for the help

[mike007]

o yea.. lol the Sybon lol

sorry

[zhenya]

Gene,

What are you guys talking about, Cybon? Do you mean Sybon? The middle one?

Oh, well. At least I said that all three of them would probably do the job. I was just eliminating the cheapest one.

Yeah, it is a Sybon. I'm typing too fast without checking up on the end results...
It may be the cheapest on that website but it is not this cheap on many others.
Check out here and read the description of it. I bought mine 4 years ago and I paid I think $89.00 instead of $114. Now they sell them for under $50. :eek3:
Anyway, it is a very nice refractometer and comes with distilled water vial for recalibration purposes.
The only reason I recalibrated mine with seawater calibration fluid is not to remember to mix exchange water with a tad higher salinity to achieve salinity of 35ppt. You have to know me to understand why I did that.

[mike007]

so would the calibration fluid be necessary? i will be using it for a future reef tank. is there any difference in accuracy?

PS. other equipment that i would need to switch to reef. i currently have a sump(with posban and 2 bags of chemical filter mediaDr G's Marine Aquaculture - Chemical Filter Media). looking at either protein skimmer, uv sterilizer or refugium. which of these would be most beneficial for this purpose? i can only get one at a time due to finances.

[Ninong]

so would the calibration fluid be necessary?

That's for you to decide for yourself. Read that other thread and then make up your own mind.

is there any difference in accuracy?

The accuracy depends entirely on the user. Read the other thread.

PS. other equipment that i would need to switch to reef. i currently have a sump(with posban and 2 bags of chemical filter mediaDr G's Marine Aquaculture - Chemical Filter Media). looking at either protein skimmer, uv sterilizer or refugium. which of these would be most beneficial for this purpose? i can only get one at a time due to finances.

The protein skimmer should be your next purchase. You don't need the UV filter and a refugium is a nice future addition if and when you decide to get one.

[mike007]

The accuracy depends entirely on the user. Read the other thread.

i cant fully understand that thread... can you explain how the accuracy would vary with the user and how would be the best and/or easiest way to be the most accurate?
thanks

[Ninong]

Hi Mike,

Okay, sorry about that.

Summary: Buy one of those refractometers.

The scale is not designed for seawater (tankwater). The scale was designed for sodium chloride (NaCl) solutions (brine). Therefore, the readings are not seawater readings, but that's NOT a problem.

You should strive to maintain 35 ppt salinity in your aquarium and certainly no less than 34 ppt.

When the scale in your refractometer says you have 36.5 ppt, that means you really have 35 ppt seawater salinity. The scale will have a line for 36 ppt and a line for 37 ppt, so 36.5 would be in the middle.

You can do what I did and just make sure that your seawater (tankwater) measures 36 ppt on your refractometer's ppt side of the scale. That would mean that your true salinity is slightly less than 35 ppt, which is fine.

Forget about the specific gravity side of the scale and don't report your salinity in specific gravity units. In case you're curious, if your tankwater measures exactly 36.5 ppt on the salinity side of the scale, that means that your specific gravity is exactly 1.0264 or 35 ppt seawater salinity. But we're not interested in specific gravity at all -- not in the least. We're only interested in salinity.



P.S. -- Your refractometer will come from the factory already calibrated. You can check the calibration at any time by placing a couple of drops of distilled water on the plate. Distilled water should read 1.000. You don't have to do anything else. You don't have to purchase the 53 mS calibration fluid to re-calibrate your refractometer like zhenya did. He was just being cutesy! Just leave it the way it came from the factory. It's not a seawater refractometer but it will work absolutely fine. You will be very happy with your purchase.

[mike007]

ok thanks NINONG