Little Shop of Coral
DD Seawater Refractometer
DD Seawater Refractometer
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True ‘Seawater’ calibrated refractometer.
(Includes a small vial of Di water for zero calibration)
What’s different between our NEW refractometer and others you might ask? Almost all, if not all, of the refractometers currently available to the aquarium hobby are designed for measuring saltwater (sodium chloride or brine solution) and not true ‘seawater’. Although seawater is mostly sodium chloride it also contains other elements such as magnesium and calcium that change the refractive index slightly and will give a slightly different result.
The most common symptom of this difference in refractive index can be seen when mixing up salt as per salt manufacturer’s instructions and achieving a solution strength where it appears, through testing, that the levels of elements are lower than stated by the manufacturer. In actual fact all of the levels are low as the salinity is not as high as the aquarist believes – we have all seen low Ca or Mg for a given SG with almost all brands of salt.
It turns out that a 35ppt solution of true seawater has the same refractive index as a 36.5ppt solution of brine and so when using a brine/salt refractometer the salinity is likely to be low by 1.5ppt. This can be allowed for by the aquarist but only if they are aware of the difference.
After extensive development, D-D’s new refractometer addresses this issue, giving true salinity results when correctly calibrated and greater accuracy than previously attainable.

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LIGHT
LOW: Place coral at the bottom of the tank. Depending on the type, coral may need to be placed off sand and therefore mounted on a ceramic disc of piece of rock.
MEDIUM: Place coral at mid-range of the tank. Best placed/glued on top of a rock scape at mid-range height.
HIGH: Place coral from mid range to just below water level. SPS coral are shallow growing so they require and are able to tolerate intense light.
FLOW
LOW: Most soft coral do well with a small, gentle pulse. There are certain corals that can even be placed in areas of indirect flow, meaning places aside a rock structure or set into a entrance to a cave style space.
MEDIUM: Many LPS types of coral prefer medium pulse current. Most Euphyllia or corals that have more tissue structure connected to their skeleton, don’t like to be in a high flow area like the direct flow of the wave pump.
HIGH: Similar to high light, SPS enjoy being in some heavy current. Most LPS and SPS that branch encrust or plate prefer high flow that simulates the top water waves.
SKILL
ENTRY: While some may say beginner level, "Entry" is a good term to be used when starting out in the world of corals and marine life. Prior to adding livestock, you want to ensure that your reef has the proper parameters including zero levels of ammonia and nitrite. Seeing traces of nitrate in your waters is a good sign - just keep them at a lower level of 2ppm to 10ppm. Maintaining correct temperature and salinity are a huge factor to stable parameters. Starting to monitor your PH, alkalinity, calcium and magnesium is a great habit to get into to keep a successful reef.
While some soft coral don’t require too much light, having a proper reef light that puts out the proper pars is very important. You'll also want to have a good amount of flow and protected rock areas, as placing corals in their happy spot is ideal for success.
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