Any of the below listed devices gains us the ability to further examine our water parameters and increases our knowledge of the many factors which can effect the quality of life for our aquatic pets. Some of the devices are "must haves" while others are meant to be used for monitoring other equipment such as when using ozone. Sadly it seems that the instructions that come with such devices are lacking much needed information that we would apply or need to know concerning saltwater itself and the numerous compounds and interactions that effect what it is that we are testing for, or what ranges are acceptable for our systems.

T.D.S. METERS  -  These units have become popular for checking the freshwater output of reverse osmosis and deionization units, by doing so, one can tell with much greater ease, when such filtering cartridges need to be replaced. I feel other than for those purposes, they have no real use pertaining to our aquarium system's salt water.  Quote : " Since TDS meters are often used to test water "purity," it is important to understand what they do not detect. As conductivity meters in disguise, TDS meters will only detect mobile charged ions. They will not detect any neutral (uncharged) compounds. Such compounds include sugar, alcohol, many organics (including many pesticides and their residues), and unionized forms of silica, ammonia, and carbon dioxide. These meters also do not detect macroscopic particulates, as those are too large to move in the electric fields applied. So if you see "rusty" looking water from iron oxide particulates, that won't be measured. Neither will anything else that makes the water look cloudy. Bacteria and viruses also won't be detected. "

SALINITY MEASURING DEVICES  -  As usual within this hobby, there are more ways than one to accomplish any given task. Measuring the salinity levels of our system's water is no different. Of course as with any devices, some are better than others, both in accuracy and for some of us, ease of use is also of great importance.

  Refractometers  -  The best and most accurate way to test for salinity. Recently the price of such units has come down enough to allow any hobbyists to be able to afford one, and with most units now having automatic calibration included, they are also much easier to use. I have to strongly recommend that you seriously consider purchasing one simply due to their accuracy.

    Swing Arm Hydrometers  -  The most commonly used devices, and probably the easiest to use. There is nothing technical about their use which requires nothing more than filling them up to a set level and take the reading. The only concern with their use is in ensuring there are no bubbles sticking to the swing arm which would of course, make the swing arm more buoyant and cause an inaccurate reading.

      Floating Hydrometers  -  These units, to put it bluntly, I find to be a real pain to use since they must be temperature calibrated in order to get an accurate reading. Of which I never seem to be able to trust and often resort back to a swing arm type to put any doubts to rest.

O.R.P. METERS ( oxication reduction potential )  -  " Is a measure of the relative oxidizing power of the water. It has often been recommended to aquarists as an important water parameter, and some companies sell products (equipment and chemicals) designed to control ORP. Many who recommended ORP control have convinced aquarists that it is a measure of the relative "purity" of aquarium water, despite the fact that this has not been clearly demonstrated. ORP, at its heart, is very, very complicated. It is, perhaps, the single most complicated chemical feature of marine aquaria that aquarists will typically encounter. It is not hard just for aquarists who are not scientists. "

P.A.R. METERS  -  " PAR meters (also called quantum meters) are the preferred instruments for measuring light intensity when photosynthesis is involved. Ideally, quantum meters measure (and report as equal) the amount of energy in light wavelengths between 400nm and 700 nm, and report it in units of micromol per square meter per second (µmol·m²·sec). Full intensity sunlight is generally ~2,000 µmol·m²·sec. 'Micromol' is the preferred unit for reporting purposes, as opposed to 'microEinstein', a unit that is commonly used in older literature. However, any measure of PAR or PPFD (either µmol·m²·sec or µE·m²·sec) are still somewhat of 'outlaw' units, not recognized as SI units, and something of buzzwords to those obsessed with botany or phycology. "

  -    Fun Times With A Quantum Meter  -  A very indepth and excellent article by Brian Plankis (Dibs Forum), which not only shows you how to use such a meter, but also provides excellent tips, with results, showing you what can be done to increase the efficiency of your light system.

ELECTRONIC CALCIUM MONITORS  -  " Ion selective electrodes consist of a membrane that responds electrically to the presence of specific ions in solution. In a sense they are similar to pH electrodes that are sensitive to H+, but these respond to other ions instead. In the case of calcium selective electrodes, the membrane material is typically PVC (polyvinylchloride) that has been modified to be selective for calcium. "

OZONE GENERATORS / REACTORS  -  " Ozone is often used by reef aquarists to "purify" the water. To most aquarists that means making the water clearer, and it certainly does that in many cases. How to optimally accomplish that task without risking the aquarium inhabitants' or the aquarist's health, however, is not always obvious. This article is the second in a series that discuss the details of ozone and its use in reef aquaria. "

PH PROBES  -  " The success or failure of pH measurement depends on the proper application of the probe and proper subsequent maintenance of the probe. The procedures described within apply to the most common pH probe in use today and that is the flat surface combination pH probe.
  With that said, I have yet to hear of anyone who had a pH probe that was accurate, as such, I would trust and depend upon a test kit before I wasted my money on a probe that I could not trust. "

MEASURING PH WITH A METER  -  " This article describes how pH meters work, how to select one to use, and how to best use it to measure the pH of a reef aquarium. "

  TEST KITS  -  A subject very near and dear to me since an expired test kit, and my not knowing how to check the expiration date had caused me to lose a good deal of time and effort with my keeping more than just corals within my reef system. As such, I am trying to gather as much information as possible, detailing how one goes about knowing their particular test kits expiration dates. Some manufacturers stamp the box with a readily visible expiration date while others are not as obvious and instead "hide" such information simply as a lot number "made date", which you then have to know how long a particular test regeant is good for beyond that date.

Aquarium Pharmaceuticals, Inc.  -  This is one that requires you to find the test regeants made date, which is stamped on the front of each bottle.  The various test kits have an avearge shelf life of three years after the manufactured date. In the photo example, this particular bottle was filled during May of 2005, which means that it is good up untill May of 2008 if unopened. Once opened, they are good for up to one year, as long as that one year still falls under the shelf life expiration date. Which for this particular bottle, I would open and use it by May of 2007.

Sera Products  - This brand is thankfully obvious as to its shelf life expiration date. Again, I would open and use the test kit(s) one year prior to its shelf life expiration date. 


Salifert Test Kits - Another one that is quite obvious as to its expiration date.  As with all test kits, they are only good for one year after they have been opened/used.


 Important:  This is the new version that requires only 2 ml of sample water and those older test kits that require 3 ml of sample water should not have their reagents used as they are of a different concentration and will give you incorrect results.

The contents of the Magnesium Test Kit


  Remove the blue spoon/cap and with the 2 ML Syringe, add 2 ml of aquarium water to the vial.  Reagent Mg-1 will be needed next.

  Add 4 drops of Mg-1

  Swirl the vial gently for 30 seconds.

  Add 1 level spoon of Mg-2 to the test vial

  Swirl the vial gently for 10 seconds, the liquid should turn purple.

  Place the plastic tip firmly on the 1 ml syringe.  It is important that this tip be used as its volume is part of the syringe's measurement.

  Place the syringe into the Mg-3 and draw the liquid in until the lower end of the black black syringe part is at the 1.00 ml mark.  It is common for some air to be drawn in also which can be removed by holding the syringe upright (tip up) and rapidly "flick" or "tap" the syringe to force all the air up to the tip (just like you see in the movies), once all the air is at the tip, push the plunger in to force out the air and then reinsert the tip back into the Mg-3 regeant and draw in more liquid until you are at the 1.00 ml mark again. This will ensure you have exactly 1.00 ml within the syringe.

  Even with tapping to remove the air, it is okay to have a bit of a bubble left over just as long as you pull the plunger back to where the bottom of the bubble is at the 1.00 ml mark and there is a full 1.00 ml of regeant within the syringe.

  Start adding the Mg-3 with the 1 ml syringe to the test vial drop by drop.  After each drop is added, gently swirl the vial for a few seconds and keep repeating until the color of the vial's water changes from purple to either blue or gray, which ever color comes first.

  Once the test vial's water has changed to either blue or gray,  Stop!

Hold the syringe with the tip facing upward and read the position of the upper end of the black syringe part.  Each small mark or division on the syringe corresponds to 0.01 ml In the example shown in the photo, it reads as .23 and equates into  1,155 ppm of magnesium.

 Using the example shown, the equation is :

    1.0 ml - .23 ml = .77 x 1,500 = 1,155 ppm magnesium.

Any remaining Mg-3 regeant can be squirted back into the Mg-3 container and then rinse the used vial and syringes in distilled water and allow to air dry before placing back into the test kit's package.

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