Color Change in Salifert Test Kits...how do I know when it's done?

[ajm83]

In BigJohnny's pic there, I always go to the last colour on the right. It says "orange red or pink" in the instructions and to my eyes all the others are more of a purple colour.

I've never had a reference solution included in any Salifert kit I've bought, so it's guesswork based on the instructions.

 

[BigJohnny]

In BigJohnny's pic there, I always go to the last colour on the right. It says "orange red or pink" in the instructions and to my eyes all the others are more of a purple colour.

I've never had a reference solution included in any Salifert kit I've bought, so it's guesswork based on the instructions.

Yea about 99% of us always went to the right lol.

 

[shred5]

Use Hanna alkalinity Checker..
I was reading the majority of men actually see color worse than women, partially color blind or something like that. So let your girlfriend or wife look at the color.

 

[BigJohnny]

Use Hanna alkalinity Checker..
I was reading the majority of men actually see color worse than women, partially color blind or something like that. So let your girlfriend or wife look at the color.

Or an alkalinity monitor that uses pH based titration

 

[Randy Holmes-Farley]

Or an alkalinity monitor that uses pH based titration

If you use a color change kit, if you stick a pH meter in it, you can get to the exact pH (4.2-4.5) and check the color. Then always use that color.

 

[JimWelsh]

I wonder where Jim is getting the end point being violet?

From doing this:

If you use a color change kit, if you stick a pH meter in it, you can get to the exact pH (4.2-4.5) and check the color. Then always use that color.

You can read more detail here: DIY Alk test discussion thread

 

[Dcook8]

This really brought me back to undergrad chem lab. Titration in a real life application

 

[Dcook8]

Thèse tests brought me back to undergrad chem lab. Titration in a real life application

 

[stevieduk]

i gave up with this brand of kit after about 2 hours , could not tell the blue to violet change over and then when you reverse the test and put the agent back in till it goes clear against a sample, well aquarium water has a slight yellow tinge to it so how do you get them to match again. impossible.
I threw it in the bin and now use " All for Reef " 15 ml every 2 days for my tank, chemicals in it are all balanced and my tank has never looked so good, corals growing great, just test for nitrates now

 

[bryan3536]

I’ve been using API kit for Alk and Calc, recently bought a Salifert for Mag, and last week bought a Hanna Alk checker. Good news is my Alk results using the Hanna and API test were identical, which gave me a little more confidence I was using the API kits correctly. The API for Calc is a bit tedious (you have to add 10 drops of first solution, then 15+ of second (capping and turning over test tube between drops after 15) but it does give you a “warning” color change before it hits dark color and stops. No ambiguity there.

The Salifert Mag though is tough! I cannot for the life of me see the color change, and I do not understand the directions when it talks about how to fill the syringe with the reagent - I go to the end of the black stopper but I always seem to have a decent amount of air and put in the entire syringe without a color change. Either my Mag is off the chart - which it could be, I had to do a bunch of water changes recently and it’s a newer tank with just a handful of frags - or I’m doing it wrong.

I hear the concerns about the Hanna needing to be calibrated over time, but the simple process of getting an actual number without checking colors is HUGE.

 

[bryan3536]

I’ve been using API kit for Alk and Calc, recently bought a Salifert for Mag, and last week bought a Hanna Alk checker. Good news is my Alk results using the Hanna and API test were identical, which gave me a little more confidence I was using the API kits correctly. The API for Calc is a bit tedious (you have to add 10 drops of first solution, then 15+ of second (capping and turning over test tube between drops after 15) but it does give you a “warning” color change before it hits dark color and stops. No ambiguity there.

The Salifert Mag though is tough! I cannot for the life of me see the color change, and I do not understand the directions when it talks about how to fill the syringe with the reagent - I go to the end of the black stopper but I always seem to have a decent amount of air and put in the entire syringe without a color change. Either my Mag is off the chart - which it could be, I had to do a bunch of water changes recently and it’s a newer tank with just a handful of frags - or I’m doing it wrong.

I hear the concerns about the Hanna needing to be calibrated over time, but the simple process of getting an actual number without checking colors is HUGE.

 

[Ron Reefman]

Thanks Randy for the API color explanation. I was told many years ago to go to the end color, but I never understood the process. I'm a physics guy, not a chemistry guy. Now it makes perfect sense! Knowledge will set you free!

I'll follow to watch the discussion on the Salifert color change as I use API for my primary testing and Salifert as a back up and for my Mg test.

 

[taricha]

The Salifert Mag though is tough! I cannot for the life of me see the color change, and I do not understand the directions when it talks about how to fill the syringe with the reagent - I go to the end of the black stopper but I always seem to have a decent amount of air and put in the entire syringe without a color change. Either my Mag is off the chart - which it could be...

First, trust the directions on ignoring the air bubble. Start the plunger at 0.00, submerge tip, draw plunger up to 1.00. Then you know for certain you have pulled in 1.00ml. Air bubble is irrelevant.
Secondly, try adding more of the reagent. The color change is real and quick (usually a 0.01 makes the difference) and dark.
The kit maxes at 1500 (using 1.00ml) and we target 1300+, so you could be less than 20% high and be "off the chart". Its very easy to do.

 

[Randy Holmes-Farley]

i gave up with this brand of kit after about 2 hours , could not tell the blue to violet change over and then when you reverse the test and put the agent back in till it goes clear against a sample, well aquarium water has a slight yellow tinge to it so how do you get them to match again. impossible.

Are you talking about the Salifert calcium kit?

 

[Pjhjr]

A question based on Randy's Cheap Electronic Eyeball comment. We are about to buy an Apex system to automate our tank and are choosing Apex primarily because of the Trident auto testing coming out "soon." Should manual titration be used periodically to test results from all electronic testing devices? A recent thread commented that Milwaukee salinity checker, which we happily use as it is quicker and easier was not as accurate as using a hydrometer. Now I am wondering if we need to use the hydrometer periodically to check the Milwaukee results. By the way, thanks to everyone for this site. As new reefers we are learning everyday from the collective experience of member's comments.

 

[Randy Holmes-Farley]

A question based on Randy's Cheap Electronic Eyeball comment. We are about to buy an Apex system to automate our tank and are choosing Apex primarily because of the Trident auto testing coming out "soon." Should manual titration be used periodically to test results from all electronic testing devices? A recent thread commented that Milwaukee salinity checker, which we happily use as it is quicker and easier was not as accurate as using a hydrometer. Now I am wondering if we need to use the hydrometer periodically to check the Milwaukee results. By the way, thanks to everyone for this site. As new reefers we are learning everyday from the collective experience of member's comments.

I don't think a different method is any better than checking your primary method with an appropriate standard.

 

[Sal Amadeo]

I have high nitrates and my corals aren't doing good, I just started on red sea no3 po4-x remover. any suggestion?

 

[JimWelsh]

I have started another thread that is at least partially relevant to this thread: Alkalinity titration endpoint pH & Salifert endpoint color

 

[Reefahholic]

I like Salifert, but the other night I tried their Strontium test. I know Strontium isn't considered to be important by many, but I figured I would at least try it for myself. That Salifert test was horrible. The color change was so hard to observe it was ridiculous. I tried it 3x and it was so bad that I literally threw the test in the garbage on the 3rd try.

I use Red Sea now for the other tests (CAL and Mag) because it's a dramatic color change. I think the only other test kit I saw for Strontium was Seachem.

I use Hanna for ALK and PO4. Nyos for NO3.

 

[JimWelsh]

I like Salifert, but the other night I tried their Strontium test. I know Strontium isn't considered to be important by many, but I figured I would at least try it for myself. That Salifert test was horrible. The color change was so hard to observe it was ridiculous. I tried it 3x and it was so bad that I literally threw the test in the garbage on the 3rd try.

I use Red Sea now for the other tests (CAL and Mag) because it's a dramatic color change. I think the only other test kit I saw for Strontium was Seachem.

I use Hanna for ALK and PO4. Nyos for NO3.

Yeah, the Salifert strontium test is challenging, to say the least. I never have tried the Seachem Sr test kit. Strontium is really challenging to do in a hobby-level test kit, because it doesn't really behave that differently than calcium when it comes to the kinds of tests available without a bunch of expensive equipment. Calcium and Magnesium behave differently enough that you can pretty easily tease them apart, e.g., using a hydroxide to precipitate out the Mg when doing a Ca test. But Sr really behaves an awful lot like Ca when it comes to these tests. Saying it another way: The truth is that when you are testing for Ca, the answer you are getting is pretty much the combination of Ca + Sr.