whats causing the swing?
 

What is the short of the long when my alk levels drop 1meq/l in 1 day? For now I am trying to keep my alk levels steady at 4 meq/l but i am having a hell of a time. And I know its stressing stuff out. I have been using baking soda to keep it constant. Which may not be the best thing but was told that it will work. And I am testing with hagen test kits. But I figure since I am getting a constant swing in alk levels that my test kit is reading correctly. I know you all prefer salifert and I am ordering them now. In the meantime what is causing the alk level to swing so much??

What kind of Salt are you using??

What are your calcium, magnesium and alk/dkh reading? All 3 are very important and I suspect that one of them is out of whack - probably magnesium - for you to be having that kind of trouble maintaining alk. I am glad you have order Salifert test kits as they do give you a more accurate result.

I thought magnesium only affected calcium levels??
Alk - fluctuates between 7 dkh and 10 dkh. In a matter of 3-4 days.
calcium - 360 ppm
magnesium unknown....

Salt is I/O. And when i tested the salt from a new mix left 24h. to circulate. I got low reading on both alk and calcium.
alk - 6 dkh
calc - 280 ppm
magnesium unknown

reply
 

MG definately effects both levels. If MG is low, Calcium can't be utilized efficiantly and it throws your ALK out of whack. I was having difficulty keeping my PH and ALK up, so I started dosing MG more and it solved my problem.

A Simplified Guide to the Relationship between Calcium, Alkalinity, Magnesium and pH by Randy Holmes-Farley

A great read! :biggrin: