New Salifert Calcium give a very different result

[Blake423]

Hi,

I use salifert test kit for all the parameters and I keep my calcium level around 420.
I just bought a new salifert calcium test kit because the old one is finished, and the new kit has a new method.
Guess what, the first test of the new kit shows 480.
It has been about 2 days between the last test of old kit and the first test of new kit, no water change and no new coral in between and I am dosing, the calcium level are very stable in the past.
So I am confused...should I bring down the calcium level back to where I want? Or just keep to the level the new kit show (480)?

Do you guys have similar experiences?

 

[blaxsun]

As a testing kit gets older the % variance can change over time, so it's not entirely surprising. So you're dosing or not dosing? 480 is perfectly fine, so I'd probably look to lower it with subsequent water changes.

 

[LgTas]

I found the same thing. New method reads much higher than old

 

[Waynefish]

I found the same thing. New method reads much higher than old

Same here. I thought the new test was defective. I bought an API test kit to check. Both new test kits agree. I believe the old one was off due to age.