I recently ordered calcium and alkalinity test kits from Elos (a vendor on the forums) and decided to do a friendly little head to head comparison with the ever popular Salifert test kits. This is to compare easy of use and repeatable results and not an accuracy test; that would require a laboratory and some serious money.
I mixed up a batch of salt water using Tropic Marin Pro Reef the night before, and checked the salinity with a refractometer. On the morning of the test, the salinity was 35 ppt (1.026 for SG) and the pH measured 8.1-8.2 using a Salifert pH test kit. All vials were rinsed with tap water and then with this makeup water prior to each test. Let's get started!!
Here are the competitors:
I started with the Elos KH kit first. It's pretty simple; add 5 ml of test water with the provided syringe. Then just begin adding regeant one drop at a time, making sure to count the drops. 1 drop equals 1 KH. When you add the first drop or two, the solution turns blue.
Keep adding one drop at a time until the test turns yellow.
The solution went from blue to yellow quite abruptly; there was no in-between colors. I performed this test five times and then once on my tank water. Here are my results:
Test 1 - 8dKH
Test 2 - 7dKH
Test 3 - 7dKH
Test 4 - 9dKH
Test 5 - 8dKH
Tank water - 7dKH
Now for the Salifert KH tests. This required a few more steps to perform. Add 4 ml of test water via supplied syringe. Add two drops of KH regeant. The sample turns blue.
Using the supplied syringe, begin dropping the second liquid until it turns pink.
I performed this test five times and here are the results:
Test 1 - 9.3dKH (3.31 mg/l)
Test 2 - 9.6dKH (3.43 mg/l)
Test 3 - 9.3dKH (3.31 mg/l)
Test 4 - 9.3dKH (3.31 mg/l)
Test 5 - 9.6dKH (3.43 mg/l)
Tank water - 7.4dKH (2.63 mg/l) I know, I know, add a little buffer!!
Next up on the list is the calcium test. I started with the Elos kit first and attempted to perform 5 tests. It's not as simple to do as the KH test and needed a few more steps.
Add 5ml of test water to the test vial using the supplied syringe. Add 7 drops of regeant A, then 1 small spoon of the dry regeant B. The test liquid will be pink.
Slowly add one drop at a time of regeant C, making sure to count the drops. Do this until the test liquid turns blue.
Multiply the number of drops by 25, and you have your calcium in ppm. Here are my results:
Test 1 - 450ppm
Test 2 - 475ppm
Test 3 - 450ppm
I had to stop here as I ran into an issue; the test vial is made of glass. While removing the cap (this is emplaced after adding regeant B and shaking for a few seconds to dissolve the granules), the vial broke. I was not overly rough with removing the cap, but you do need to dig your fingernails underneath it to remove it.
Now, onto the Salifert calcium test. Add two mL of test water with the provided syringe. Add one scoop of regeant 1 and 8 drops of regeant two and swirl for 10 seconds. The liquid will turn pink.
Use the graduated syringe and drop regeant 3 until the solution turns blue. Read the graduated syringe and look up the values on the provided chart. I performed this test three times.
Here are my results:
Test 1 - 450ppm
Test 2 - 450ppm
Test 3 - 470ppm
My conclusion: Alright, first and foremost I am a hobbiest and not a scientist. With all due fairness to Elos, I have absolutely no practice with their kits. I simply removed them from the box, read the instructions, and performed the tests. I have been using Salifert kits for almost a year and am quite adept at using them without the instructions. The Elos KH kit is certainly easier to use, but the results seem to jump around much more than the Salifert. Again, I think this may be due to a lack of practice, though it's pretty straight forward. Also, if you or I lose count of the drops, you have to start all over; I may have done this and not realized it. With the Salifert, the graduated syringe can be put down, and it will still read the same.
As for the calcium tests, I was rather bumbed out with the test vial breaking so quickly. Again, don't lose track of the number of drops added, as you may skew the results. Both test kits measured calcium at the same level.
Either one of these kits would work for the hobbiest and are not very expensive. I hope this simple comparison will introduce new reefers to different products on the market and allow them to make a more informed decision. Again, I feel the need to stress that this was not a test of accuracy, just repeatable results and ease of use.
I mixed up a batch of salt water using Tropic Marin Pro Reef the night before, and checked the salinity with a refractometer. On the morning of the test, the salinity was 35 ppt (1.026 for SG) and the pH measured 8.1-8.2 using a Salifert pH test kit. All vials were rinsed with tap water and then with this makeup water prior to each test. Let's get started!!
Here are the competitors:
I started with the Elos KH kit first. It's pretty simple; add 5 ml of test water with the provided syringe. Then just begin adding regeant one drop at a time, making sure to count the drops. 1 drop equals 1 KH. When you add the first drop or two, the solution turns blue.
Keep adding one drop at a time until the test turns yellow.
The solution went from blue to yellow quite abruptly; there was no in-between colors. I performed this test five times and then once on my tank water. Here are my results:
Test 1 - 8dKH
Test 2 - 7dKH
Test 3 - 7dKH
Test 4 - 9dKH
Test 5 - 8dKH
Tank water - 7dKH
Now for the Salifert KH tests. This required a few more steps to perform. Add 4 ml of test water via supplied syringe. Add two drops of KH regeant. The sample turns blue.
Using the supplied syringe, begin dropping the second liquid until it turns pink.
I performed this test five times and here are the results:
Test 1 - 9.3dKH (3.31 mg/l)
Test 2 - 9.6dKH (3.43 mg/l)
Test 3 - 9.3dKH (3.31 mg/l)
Test 4 - 9.3dKH (3.31 mg/l)
Test 5 - 9.6dKH (3.43 mg/l)
Tank water - 7.4dKH (2.63 mg/l) I know, I know, add a little buffer!!
Next up on the list is the calcium test. I started with the Elos kit first and attempted to perform 5 tests. It's not as simple to do as the KH test and needed a few more steps.
Add 5ml of test water to the test vial using the supplied syringe. Add 7 drops of regeant A, then 1 small spoon of the dry regeant B. The test liquid will be pink.
Slowly add one drop at a time of regeant C, making sure to count the drops. Do this until the test liquid turns blue.
Multiply the number of drops by 25, and you have your calcium in ppm. Here are my results:
Test 1 - 450ppm
Test 2 - 475ppm
Test 3 - 450ppm
I had to stop here as I ran into an issue; the test vial is made of glass. While removing the cap (this is emplaced after adding regeant B and shaking for a few seconds to dissolve the granules), the vial broke. I was not overly rough with removing the cap, but you do need to dig your fingernails underneath it to remove it.
Now, onto the Salifert calcium test. Add two mL of test water with the provided syringe. Add one scoop of regeant 1 and 8 drops of regeant two and swirl for 10 seconds. The liquid will turn pink.
Use the graduated syringe and drop regeant 3 until the solution turns blue. Read the graduated syringe and look up the values on the provided chart. I performed this test three times.
Here are my results:
Test 1 - 450ppm
Test 2 - 450ppm
Test 3 - 470ppm
My conclusion: Alright, first and foremost I am a hobbiest and not a scientist. With all due fairness to Elos, I have absolutely no practice with their kits. I simply removed them from the box, read the instructions, and performed the tests. I have been using Salifert kits for almost a year and am quite adept at using them without the instructions. The Elos KH kit is certainly easier to use, but the results seem to jump around much more than the Salifert. Again, I think this may be due to a lack of practice, though it's pretty straight forward. Also, if you or I lose count of the drops, you have to start all over; I may have done this and not realized it. With the Salifert, the graduated syringe can be put down, and it will still read the same.
As for the calcium tests, I was rather bumbed out with the test vial breaking so quickly. Again, don't lose track of the number of drops added, as you may skew the results. Both test kits measured calcium at the same level.
Either one of these kits would work for the hobbiest and are not very expensive. I hope this simple comparison will introduce new reefers to different products on the market and allow them to make a more informed decision. Again, I feel the need to stress that this was not a test of accuracy, just repeatable results and ease of use.
