Hanna Calcium - **600** WTF?!

[LebaneseDlight]

I have a Hanna Calcium tester, and the first time I used it, I got 460. OK, makes sense. I use Tropic Marin Pro salt, 20% weekly WC and don't dose anything (yet). Alk is at 158 (why so high?) and Mag at 1250. I have mostly LPS, two small SPS frags and two new, 4" Maximas. Since getting the Maximas (last week), I've been testing daily, and keep getting a flashing 600 for Calcium. Again, I haven't dosed ANYTHING! Evar! I heard Hanna Ca meters have a reputation of bein defective... I will use an API kit tonight to compare. Any preliminary thoughts?

[Deckoz2302]

MAKE SURE you wipe all your fingerprints off of the calibration and test vial with a microfiber cloth....

[NanoCuber1]

MAKE SURE you wipe all your fingerprints off of the calibration and test vial with a microfiber cloth....

 

+1 yeah they are really finnicky, wipe the probe down.

[Spirofucci]

I have the Hanna Ca checker. It is a very poorly designed piece of crap. There are way too many sensitive variables in the process. The two main problems are that you are only using 0.01 ml of tank water to test. So if you are off by only a 0.001 ml it can throw the whole thing off. In addition, you must use lab grade water for the rest. of the 0.9 ml. If there is any Ca in your RODI it will also throw the whole thing off and cause the meter to read > 600.

 

Some people like theirs, but I suggest you test the exact same sample 10 times and see what you get before you trust it enough to dose.

 

There are quite a few threads here and on RC regarding this. I have spoke to at least three Hanna techs on the phone and one even admitted that they never should have gone to market with it.

 

Having said that, I have the Alk tester and the hand held pH meter and am very happy with them because they are easy and verifiable.