question about calcium test

[treesprite]

When doing the drops for the calcium test and looking for the "end point", am I supposed to shake the tube between drops and go by the color of the whole tube, or not shake the tube and go by when the color turns blue as the drop first hits the water?

 

I have been shaking the tube between drops and ending up with outrageously high readings, like up to 27. The water at the surface turns blue MUCH sooner if going by the on-contact color change.

[Krewlor]

I am not sure what test kit you are using, but my Salifert test kit says you are supposed to "swirl" between each drop. Tetra test, the last test kit I used said to shake between each use. I believe I did read somewhere on the small sample kits (1 or 2 ml water samples) you were not supposed to shake, but were supposed to swirl. The introduction of microbubbles on such a small water sample would skew the interpretation of the results.

 

I am going from memory here, and lately I don't seem to remember quite as much as I used to.

[bk_market]

what test kit r u useing? for me i swirl them.

[treesprite]

API

[lancer99]

LaMotte's Ca test kit not only provides a glass vial (unlike the cheap, unreliable/unreadable plastic vials from Salifert), but also says to "gently swirl" while "gently depressing the plunger."

 

Same method, better equipment and instructions.

 

-R