Red Sea tests -- titration endpoint, please help!

[bamf25]

I have just started using the Red Sea Reef pro tests, and have a question on the titration endpoint. Is the endpoint just as it starts to change color, or when the color solidly matches the end color on the card? Meaning as the test changes from blue to red for Ca and Mg, or from blue to red with Alk, is the endpoint just as it becomes purple or without question the final card color.

The Mg and Ca tests seem to be just fine for me, while the transition on the Alk test seems very long, so I am not sure where my endpoint is.

 

[bertoni]

I haven't used that kit. Red Sea has a forum here on Reef Central, if no one else can help.

 

[Yogre]

Red Sea also has a video on YouTube that demonstrates the use of their new alk kit, as well as the Ca and Mg tests.

Search for videos by RedSeaFish2010, you should be able to find them.

 

[DNA]

I had troubles with my Magnesium test a few days ago.
It was showing very low levels repeatedly and I ended buying another test kit.

These videos are great to clear out all doubts about the procedure.
He said "make sure it's a full drop" for some reason and perhaps that's why I got the low readings three times in a row.

You need to match the colors by they way and not stop when the red starts to turn purple.

 

[RedSea Aviad]

You have my answer on our Forum.
If any of you have further questions, I'll be happy to answer.
I'm here for you, and available on Red-Sea's Forum.
Enjoy your weekend,
Aviad.

 

[Lynnmw1208]

Just remember that the magnesium color will quickly turn back to purple after the endpoint color is reached. Calcium will not and for alk it is the first reddish color you see with no hint of purple. Watch the videos on youtube and it will help greatly

 

[Whitebeam]

Just remember that the magnesium color will quickly turn back to purple after the endpoint color is reached. Calcium will not and for alk it is the first reddish color you see with no hint of purple. Watch the videos on youtube and it will help greatly

Now for me it is exactly the opposite! Calcium always fades back to pink and magnesium clearly changes and stays there. Bizarre!

The endpoints I use after repeated testing against reference solutions are:

Alk - first trace of pink. If it is at all more pink than blue, that's my colour. This test is always high for me vs my reference solution (Coral Shop), but I don't care too much as it is very consistent (and I don't know to what end point Coral Shop calibrated their standard).

Ca - the first blue colour that does not fade back to pink. Consistent within 20ppm of reference.

Mg - first blue. This test for me is always absolutely solid and very clear. It goes from pink to blue within a couple of drops and, as I said already, it never fades back to pink. Consistent within 30ppm of reference.

Peter