Hanna DKH Reading Super low

[jhatfield]

Anyone else having issues with the Hanna DKH reagent reading in the 4 to 5dkh range? Cross checked it with an Aquaforest alk kit which read 8.5, about normal for my tank. While waiting for hanna's customer service I thought post on R2R/

A little background... I've been using it for the past three years with no issues so this caught me off guard. Foolishly, I started adding more alk to get the levels up but to no avail. Eventually everything began to get crusty, especially the return pump. Figuring something was wrong in the testing I ordered new reagent and an alk test kit from Aquaforest.

The new reagent showed normal dkh on the first use but three days later was reading ~5dkh. The AF read a more normal 8.5dkh. I can tell right away something is wrong because the color is so light, so it's not the tester itself. Guessing bad batch of reagent... ?

Side note: During the two weeks I was dosing high alk, thinking my alk was too low, my corals never looked better. Huge growth spurt and fantastic color. I have no Idea how high my alk got but it was enough to cause some precipitation. Once the new kits arrived it had been a week with no dosing whatsoever so things had time to settle down.

 

[P-Dub]

You may have done this already and forgive me if you have but, did you change out the battery?

 

[jhatfield]

You may have done this already and forgive me if you have but, did you change out the battery?

Thought about that but the battery was changed about a month prior. Before that I had a battery in there for 5 months before I had to change it.

Also, as soon as I add the reagent I can tell immediately that the color is way off even before I put it in the tester. Ends up being a very pale blue green. It's the visible color change that got me to wondering if the reagent is bad.