another alk question

[scbasser5]

Is there any thing in the reef tank that can cause the alk levels to go up?

Mine was high, I did several water changes and have turned off the CA reactor it dropped to 140 ppm.

tonights test it was up to 170 ppm.

I am not sure I trust any of these tests.

As usuall thanks for the input.

 

[Randy Holmes-Farley]

It could be a testing error or some sort. About the only thing likely to make it rise is artificial rock made from materials that leach alkalinity.

FWIW, I recommend 125-200 ppm CaCO3 equivalents for alkalinity (2.5-4 meq/L; 7-11 dKH), so there is no reason to want to lower it.

 

[scbasser5]

Thanks Randy, I knew you said it wasnt that high, was more curious as to why it tested higher last night.

I still don't know how accurate tests that rely on counting drops and watching for color changes or matching colors can be. Seems like there is plenty of room for interpetation and/or error. Who is to say the drops are equal each time? Some one like me that has trouble with color matching too. (should see the clothes i wear you would understand, LOL)

We need a more reliable way to test or not put so much stock in the accuracy of the tests. I guess just use them to check for wild variations. Every time a fish or coral doesnt look right, I start testing everything and then go to doubting my system because the test seem to vary.


Thanks again.

 

[Randy Holmes-Farley]

Some kits are more reliable and reproducible than others, and some parameters are more reproducible than others. Alkalinity should be a fairly consistent one, but some brands have a lot of noise, especially if the number of drops is low. Others, like Hach, LaMotte, Seachem, and Salifert should give reliable alk values.