KH Carer Review and Experience

[a.ocellaris]

I got this unit last month. Has anyone else played with the dilution of the concentrate reagent with the KH Carer? I found that diluting 1:8 (0.011N) using 0.01N sulfuric acid was causing a low dKH reading. Diluting to 1:9 making (0.01N) made readings match up with my Hanna checker. This made dilution for usable solution super easy, too. Adding 100 ml to 900ml of RODI for a total of 1 liter of usable reagent. Readings have been pretty steady at around 8 dKH for the past three weeks testing 6 times a day. Thinking of cutting back to four time a day now. Anyone see any long term issue of using the more diluted reagent besides saving a bit of money? Accuracy issues?

 

[tmccaff]

What kind of acid you using? I am interested in making diy for mine as well.

 

[n2585722]

What kind of acid you using? I am interested in making diy for mine as well.

I use this https://www.coralvue.com/alkalinity-testing-machine-concentrated-reagent .

 

[a.ocellaris]

I got the stuff people use for the diy Alkatronic reagent from Amazon. Labchem’s sulfuric acid 0.1N (0.5M).

 

[tmccaff]

Am I missing something how is the diy acid cheaper? I see the 4L is $69 dollars. I just ordered the Kh Carer. What you guys use for containers? I am guessing need 2 containers one for buffer other for reagent.

 

[a.ocellaris]

I agree with you, $69 for the .1N acid is not saving much money. Still a little cheaper than Alkatronic reagent that was being sold with the KH Carer when I bought my machine. You can get the more concentrated lab grade sulfuric acid and dilute it down to the 0.1N, too. Not hard as long as you have a way to accurately measure everything and are safe about it (safety goggles, gloves, acid to water, etc). A volumetric flask also comes in handy. I will be doing that in the future.

As for the container, I am using an empty one gallon vinegar jug. It’s been working just fine to hold the diluted sulfuric acid used for testing. I use the BRS jug to hold my Alk 2-part solution.

 

[n2585722]

Am I missing something how is the diy acid cheaper? I see the 4L is $69 dollars. I just ordered the Kh Carer. What you guys use for containers? I am guessing need 2 containers one for buffer other for reagent.

I use repurposed jars for mine.

 

[Mattiejay6]

I got this unit last month. Has anyone else played with the dilution of the concentrate reagent with the KH Carer? I found that diluting 1:8 (0.011N) using 0.01N sulfuric acid was causing a low dKH reading. Diluting to 1:9 making (0.01N) made readings match up with my Hanna checker. This made dilution for usable solution super easy, too. Adding 100 ml to 900ml of RODI for a total of 1 liter of usable reagent. Readings have been pretty steady at around 8 dKH for the past three weeks testing 6 times a day. Thinking of cutting back to four time a day now. Anyone see any long term issue of using the more diluted reagent besides saving a bit of money? Accuracy issues?

So I know when they first released it and used the Coralvue Solution it was recommended 1 to 9 parts, but then they drop it down. Not sure why

 

[a.ocellaris]

So I know when they first released it and used the Coralvue Solution it was recommended 1 to 9 parts, but then they drop it down. Not sure why

Thanks! I will continue to use the sulfuric acid diluted down to 0.01N since it is working for me.

 

[tmccaff]

I can't get the Kh carer to get Alk correctly. Salifert reads 9.3; Hanna 9.6; and Kh Carer reading 7.19.
What is weird is I mixed 1:8 ratio first time I used this and tested for Kh Availability on app and says no good. Went with 1:7 ratio and says it was good. I am using the Coralvue concentrated reagent.

How you make it correspond with Hanna? I am on app is it the Kh Calibration value? Right now it looks like whats in there is 16.16.

I am really lost the instructions horrible.

 

[n2585722]

I can't get the Kh carer to get Alk correctly. Salifert reads 9.3; Hanna 9.6; and Kh Carer reading 7.19.
What is weird is I mixed 1:8 ratio first time I used this and tested for Kh Availability on app and says no good. Went with 1:7 ratio and says it was good. I am using the Coralvue concentrated reagent.

How you make it correspond with Hanna? I am on app is it the Kh Calibration value? Right now it looks like whats in there is 16.16.

I am really lost the instructions horrible.

I weigh it on a scale and tare it to 0ml with the empty container on the scale. I pour in around 110ml of concentrate in the container and then multiply the actual reading by 9 to get the total weight it needs to be and I add DI water until I reach that amount. The KH calibration value lets you add in actual KH reading and it will change the 16.16 value so that it would reqd what you entered for an output. That is quite a ways off though. You might want to calibrate pH and the saltwater pump again before you change that. The pH probes tend to drift for the first week of use. Also there is a break in period on the pumps. I think mine lasted a couple of weeks.

 

[tmccaff]

You're using the Coralvue concentrated reagent? I made first batch with the one that came with unit but I ran the KH Availability test and said the reagent was no good. I am not supposed to run that first? You make 1:9 ratio? Instructions say 1:8 but I made it 1:7 maybe my issue that I am doing wrong here.

 

[n2585722]

You're using the Coralvue concentrated reagent? I made first batch with the one that came with unit but I ran the KH Availability test and said the reagent was no good. I am not supposed to run that first? You make 1:9 ratio? Instructions say 1:8 but I made it 1:7 maybe my issue that I am doing wrong here.

Mine is 1 to 8 since the first amount is a part of the weight it has to be included so that is why I multiply by 9. One unit and 8 other equal units combined is 9 units. Also you need to make sure there is not an issue with the pH reading since that will cause an error with the availability test and the KH reading. I use what came with it at first and now use the Coralvue concentrate.

 

[tmccaff]

Ok, i will recalibrate everything again tomorrow. I will make a small amount of reagent 1:8 ratio and see what happens. Thanks

 

[tmccaff]

I have packets of PH4&7 as well as PH7&10 which should I use?

 

[a.ocellaris]

I have packets of PH4&7 as well as PH7&10 which should I use?

I don’t believe you can use 10 to calibrate. Options for me were 4 & 7 and 4 & 9.18.

 

[n2585722]

You will need to use 4 and 7. The Carer does not use 10.

 

[tmccaff]

Ok last night did a test and accurate with my salifert. It came to 9.56 this morning came to 8.24. I have to check with my Salifert test. Can it be that much difference? I checked with salifert it shows .47 which is 8.3. I am wondering though why my tank would consume that much or is it because no lights on? How many tests per day? I plan on one in morning before lights and one before lights go out.

 

[n2585722]

Ok last night did a test and accurate with my salifert. It came to 9.56 this morning came to 8.24. I have to check with my Salifert test. Can it be that much difference? I checked with salifert it shows .47 which is 8.3. I am wondering though why my tank would consume that much or is it because no lights on? How many tests per day? I plan on one in morning before lights and one before lights go out.

Are dosing anything that may cause it to rise? I do dose and the last few test it was dropping even overnight which it usually goes up instead of falling. I pulled the tubing out of the fitting to check to see if it was dispensing and it must have been plugged up something fell off of it but it was where I could not see it. The next test was around 9.3 and the previous test was 8.1.The only thing I can think of is the tubing plugged up and the tubing pressurized since the pump kept dispensing. It was all dumped in when I pulled tubing out of the fitting in the sump. i now have the tip of the tubing below the water surface to see if that will keep it from happening. I had switched to a dosing pump with a lower flow rate so that may be why it started clogging up at the end. I do not use the KHC to do my dosing I did not have the clogging issue when I did use it.

 

[sevitz5]

Per the advice of others on reef2reef I have changed the number of rinses that the testing vessel gets after each test. I am trying 3 rinses from the default 1 rinse. I will see if this helps.

Where are you changing the number of rinse cycles?