Alkalinity Testing all Over the place ???

[dannyd_]

Hello all

I have been having issues with alkalinity for a little bit now. I have been testing for the past couple weeks and dosing to get it to around 9-10, and I finally have done it (I thougth). I have been testing every couple days and for about two weeks now my test kit (red sea) has been reading 9.5. I took a sample to my lfs as I do every once in a while to just confirm what I am getting and they triple tested and were getting a 6! THis seems more accurate as I have noticed montipora, gonis, and encrusters aren't happy. I have been watching videos now on how to properly test and am more confused then before. The guy at the store suggestsed that I take the tip off the syringe and then draw in the liquid, and when I do this my alk reads 10.9 vs when I leave the tip on I get 9.5. In addition to this he also mentioned some people take the tip off and then draw liquid in and out, eliminating all air bubbles. I did this and it goes up to 11. I am unsure of what is going on now, and would love any feedback as this is greatly affecting some corals. (LFS used red sea and api)

for reference:
- I am drawing in liquid to the bottom of the plunger
- I am cleaning out the vial each time, and when I store the vials I leave rodi water in them
- I am doing a drop or two past the color change to ensure it is the full color
- I am taking 10ml of water for the test

 

[ReefSlice]

Send in an icp and test your tank at the same time you collect your icp sample to see how accurate your test kits are. I personally leave the tip on, make sure there is no liquid at all in my syringe by clearing it a few times with air, then draw it up until the bottom of the plunger reads 1 ml or whatever the test asks for.