Are all aquarium refractometers like this?

Discussion in 'Equipment' started by gerbilbox, May 16, 2011.

  1. GDawson

    GDawson Guest

    Thank God you got the joke...I was beginning to worry! :bigsmile: I DO have a glass one from the days of yore but it hasn't seen the light of day in 15 years or so!

    I use a cheap knock-off POS that needs to be replaced. And yes it needs calibration everytime I use it.

    -Gregory
     
  2. bmhair03

    bmhair03 Guest

    +1 on the D-D. Scale range is nice too. 20-40ppt not 0-100ppt.
     
  3. sfsuphysics

    sfsuphysics Supporting Member

    Only for stray current :D
     
  4. gerbilbox

    gerbilbox Guest

    And an open cut to test for palytoxins? :)

    So two votes for D-D, and I also read on other forms that Vee Gee / Vital Sine makes a good (but pricier) one. Whatever, as long as it stays consistent long enough and can tolerate the trauma of being gently placed on a table, even a partial-piece-of-shit is an improvement over the piece-of-shit I have now.
     
  5. rygh

    rygh Supporting Member

    Bonus : that range seems like it would force you to calibrate with a good reference sample, and not RODI.
     
  6. GreshamH

    GreshamH Guest

    http://www.theaquariumsolution.com/specific-gravity-salinity-and-its-measurement
     
  7. GreshamH

    GreshamH Guest

    Vital is an OK unit, pretty beefy but WAY over priced. The D-D unit is better (and cheaper). I use both but much prefer the D-D unit.
     
  8. gerbilbox

    gerbilbox Guest

    My new D-D Refractometer arrived today, and it is definitely a HUGE improvement over my old one. I gave it some "light abuse" and the calibration didn't drift like my old one would. I also found it easier to read, and it has a heftier feel like the lab refractometer I used at an old job. It measured my tank running slightly high (36 ppt), but nothing dramatic. Thanks guys!
     
  9. kc

    kc Guest

    we've been using a RHS-10ATC REFACTOMETER for years and have had no problems with the calibration. It has been very reliable.
     
  10. houser

    houser Past President

    Well while not being careful I dropped my refractometer (POS) a few nights ago and severely damaged the optics. Oh well time to get a new one so this thread is timed perfectly.
    Now that I think of it I do have a hydrometer in my beermaking supplies I should bust out.
     
  11. bondolo

    bondolo Supporting Member

    I've been looking for a vendor that sells the "D-D New model seawater refractometer with auto temperature compensation". It seems that D-D previously sold a model that did not do temperature compensation and another model that was a salinity (as opposed to seawater) S.G.

    For the curious the ATC models have a big sticker which say "ATC". The salinity models are 0-100pt. The seawater models are 20-40ppt

    Any suggestions for a vendor from which I can reliably get the latest D-D unit as well as appropriate (seawater 35ppt vs. saline 35ppt) reference samples? The google results (especially the eBay ones) are ambiguous about the model being offered.
     
  12. bmhair03

    bmhair03 Guest

    I got mine at Aquatic Collection.
     
  13. GreshamH

    GreshamH Guest

    You will have a hatd time getting anything but the correct model. Any LFS thay buys from Sunlight Supply can get them.
     
  14. houser

    houser Past President

    D&D users -
    We fired up one yesterday for the first time. We had to put like 5 or 6 drops on there as the daylight plate was pretty loose and it took that much liquid to ensure that the prism didn't have air bubbles. That being said it did seem to be accurate and repeatable which is a far cry from my POS one before.
    Doesn't that seem like a lot of liquid?
     
  15. Gomer

    Gomer Honorary Member

    Should only need 1-2 drops max ime. Lid should lie flat on the glass without any fluid.
     
  16. houser

    houser Past President

    Yeah, that's what I would think too. The daylight plate was soooo loose it was just flopping around. Anybody else with that issue?
     
  17. GreshamH

    GreshamH Guest

    Thats just how they are.
     
  18. rygh

    rygh Supporting Member

    Well, comparing that problem to my Marine Depot Cheapo, that tends to rust tight ..... which is worse?
    :)

    On the other hand, I did take the above advice, and bought some refractometer calibration fluid.
    Bulk Reef Supply has it, specific for refractomers as opposed to conductivity.

    It was still dead-on perfectly accurate!

    My guess - like so many things built in China, it can be hit or miss, and I was lucky.
     
  19. bmhair03

    bmhair03 Guest

    My plate and glass always line up when closed. There is slop in the hinge design but I think that's for easier movement.
    They should have went with closer tolerances and let it "wear" in. But after the pin rusts in awhile , I'm sure it will tighten up a bit.
    As for the amount of water,I use up to the 1ml? on the dropper. Instructions say use more water and let the cover push off the extra.
     
  20. Gomer

    Gomer Honorary Member

    I have the MD one and the lid works fine. Nice and flat. No rusting, despite the fact that I often just dip the head in salt water and never rinse it off. Of course, the set screw is now frozen :p
     

Share This Page