Red Sea Pro Alk test kit results issue.

[Loki]

I've woke up early this morning to test my levels in my tank and my water mixing station.

Last week was the first time I tested my tank and my alk was low. I had a friend verify that my test kit was accurate and he got the same result with his.

Results were:

2-2-15
Alk 5.3
Calcium 425
Mag 1260

I dosed my tank with 60ml of brs alk three times in two days. It raised the alk to 8.3

So today I tested again and my alk test is not turning pink. Here are some pictures.

This is with a full ml in

 

[Loki]

Just for kicks I added a second ml in after a friend suggested to add more.

The lot# on the bottle. There is no expiration on it that I have found.

Just for comparison here is the exp on my calcium

 

[Matthias7]

I thought the end color was supposed to be orange? (Like you have pictured for alk). I beleive pink is the end color for the Red Sea calcium test

 

[Loki]

I've read the instructions, followed the pictures on this card

And watched this video.

http://youtu.be/bb4NnYOFneA

 

[Loki]

I thought the end color was supposed to be orange? (Like you have pictured for alk). I beleive pink is the end color for the Red Sea calcium test

2:25 of the video shows it purple and then he says "We are looking for a good pink."

 

[Terry4505]

The end point is one drop after it turns from blue to orange/peach

 

[doylef4i]

It doesn't matter if it goes from blue to pink or from purple to green. You are just looking for the transition from one color to another just like Terry4505 said.

 

[Terry4505]

I had the same question. I couldn't get the color on the card, no matter how much reagent I added. I double checked with my Hanna Alk Checker and it's accurate.

 

[redfishbluefish]

It doesn't matter if it goes from blue to pink or from purple to green. You are just looking for the transition from one color to another just like Terry4505 said.

This is a BIG +1


This isn't an API test were you try to match the color on the card. You are simply looking for it to change from one color to the other (regardless of the color). As you get close, add drop wise until there is no more color change.

 

[Mike J.]

I use Red Sea test kits for everything. +1 to the above about just watching for a color change. My alk test does the same thing and is not red like the card. I have come to the conclusion that THE drop when it changes color is the one you want to calculate as the most accurate.

 

[Loki]

So it's any color change then? It just didn't do anything like the video showed. So I was concerned and wanted to clarify that what I was getting was accurate or not.

 

[Randy Holmes-Farley Verified Community Expert]

The end point is one drop after it turns from blue to orange/peach

How do you know that?

 

[Randy Holmes-Farley Verified Community Expert]

If you have a calibrated pH meter, we can determine exactly when you reach the endpoint, even without any dye, and we can also say for sure what color the dye should be.

 

[Loki]

I calibrated my ph probe for my apex yesterday so I'm all for knowing more info on this!

 

[Randy Holmes-Farley Verified Community Expert]

The endpoint is about pH 4.2 to 4.5. So next time you do an alkalinity titration, see what the color is and the amount added to get the true alkalinity at that pH. A single drop of titrant will likely drop it from above that range to below it, so that is the point to call it.

I discuss such issues here:

A DIY Alkalinity Test: By Randy Holmes-Farley - REEFEDITION

 

[ChristopherKriens]

How do you know that?

+1. I have always used the measurement where the color change was complete. Sometimes it takes an extra drip to know for sure, but that isn't your reading.