I just bought the new Hana Alk and Cal and still have Aquarium Pharmaceuticals Am, Nitrite and Nitrate and seen to work well. I'll buy other Hana's when I can afford them. I sure like the digital over the colors !
I had read a few days ago about your situation, but don't recall which company it was. eek !
It read like 0, ppm Nitrate and his corals we dying, so he bought a different kit and it read 50ppm. Now, I find it hard to believe but, you never know. A lot of things could have happened.
That's why I like to buy a second brand to test against each other.
Take your time and learn that Hanna Ca kit well. Watch all their YouTube videos that apply. Every detail of the test procedure is crucial. Ca is one of the most finicky tests I've used.
If you Google, you'll see a lot of people question their Ca Checker results....it's not the tester's fault in 99.9% of those cases...it's just THAT picky about everything being right. So cut yourself slack, pay close attention to instructions and usage guidelines and practice, practice, practice!
FWIW, I would have recommended you stick to the Salifert kits for Ca (maybe alk too) unless you are blue and/or red color-blind. Those are the two color phases on both kits. Once you are familiar with them, these Salifert kits are much faster and easier to use as long as you are able to interpret the results.
Personally, I found it very reassuring to have a Salifert kit to test the same samples for Ca and alk in parallel with the Hanna. The Hanna takes practice, and this is a good way to verify if you're doing it right or not. I found that when I got it right, the Hanna was very, very close to 1:1 with the results I'd get with the Salifert. There's a margin of error inherent with each test, so you always have to allow for that...hence "very very close" and not "the same." I'd get some same, some within the margin of error. Outside the margin of error was always my fault. Fingerprint/smear on the vial, or sloppy syringe work were probably my most common goofs. Careful with those vials as they scratch easily and you'll constantly be rubbing mineral residue off of them.....their cleaning cloth (or one like it) are actually worth having. As are a set of spare vials.
The Hanna's are all very accurate, but the ones most worth having IMO are probably the Phosphate, Phosphorus (either/or, not both) and pH meters. They don't have a Nitrate meter, or that would be on the list as well. Nitrate and pH liquid tests are notoriously hard to read with any precision.
If you're tank is being run well, routine pH, phosphate and nitrate testing shouldn't really be necessary anyway.....you can always take a sample to the LFS for a nitrate or phosphate spot-check.
Hach is another place to look for Nitrate and pH liquid tests, if you must test and want accuracy. They come with a color comparator (sample box with color wheel) that makes seeing the finer color changes much more possible. Still not perfect, a bit more expensive up front, but cheap in the long run if you do a lot of testing. So something to consider, but these kits are not for everyone.
Hope this helps!
-Matt
