Below is a list of useful tips when using Red Sea test kits, a lot of these tips are standard laboratory practices which prevent cross contamination and improve on the consistency of results when testing.
It is critical to wash and dry all Vials, Syringes and Tips before doing tests and to make sure that there is no contamination between different test reagents and other contaminates.
An easy way of keeping test equipment free from contamination is to soak in a Citric Acid solution and rinse with zero TDS R/O water before drying.
When adding drops of our liquid reagents from the bottles it is very important to check that full drops come out. Sometimes there is air caught in the dropper and instead of a drop you get like a bubble burst. If this gets counted as a drop it can ruin the result of the test. This is particularly true of the calcium and magnesium tests.
Titration Syringe Tips. In order to ensure the very high resolution of the tests we have chosen a Syringe Tip that gives a drop size of 0.01ml. Our new Pro Tests use plastic tips instead of hypodermic needles to prevent possible misuse of our products.
When drawing titrant into the syringe leave the tip submersed in the titrant until the liquid has stopped rising in the syringe, if you appear to have created a vacuum in the syringe when charging with reagent ensure you have a good syringe tip indicated by being able to form a droplet dropping from the tip vertically and not spraying out, If you have a syringe which has a restricted outlet please cut off approx 1.0mm at an angle of 45 degrees from the end of the tip. This is best done with a sharp blade as scissors will tend to squeeze the plastic. This will not affect the accuracy of the test in anyway and will make the Titrator much easier to use.
It is extremely important to agitate the vial continuously while adding the titrant to make sure that there is complete mixing between the titrant and the test solution. (Our instructions state “gently swirl” we will get this changed in the next reprint of the instructions).
Please follow the instructions as accurately as possible as they are all significant. In particular the Magnesium test requires shaking of the vial after adding each drop of reagent A. This is critical to the accuracy of the test. The tests are time sensitive please use a stop watch if possible.
Magnesium. One of the important issues with the magnesium kit is being able to recognize the end point. When the blue end point is first reached is disappears very quickly. We write about this in the instructions but many do not fully understand the importance of this information. The blue colour of the end point disappears and the liquid returns almost to the previous colour (Violet). Most titrations maintain the end point when it is reached and therefore this is a very unusual instruction and differs from many other makes. Stop at the first sign of a blue liquid in the vial.
Calcium. There doesn’t seem to be any concerns with identifying the end point on the Calcium test but for completeness, stop when you see a blue liquid in the vial.
Alkalinity. You are looking for a pink colour endpoint In fact the true end point of the KH test is one drop before the pink which is an almost colorless point which really is difficult to see. Since one drop of KH is equivalent to 0.15 dKH, (which is insignificant for aquariums) we decided to set the end point at the one drop passed the true end point as we thought that it is much easier to identify. Therefore look out for an almost colorless liquid in the vial and stop at the first sign of pinkness.
The Red Sea test kit videos can be found here:http://www.redseafish.com/index.aspx?id=4225
Technical Support Manager