How long is Alkinity and Calcium additive good for?

[Kayceejake]

I buy ALK and CA bulk from LFS in 1 gallon jugs. I tore down a tank and just started a new one. I have jugs of CA and ALK that have been sitting for about a year. Are they safe to use after that long?

Thank you in advance for your input!

 

[Rico's Reefnecks]

Should be OK in principle - if you have lots of precipitate I might think twice given that its not all that expensive (compared to other things in this hobby anyway!)

But I'm sure plenty of people are dosing from reservoirs that are at least this old. One other post I found:

DIY 2 part, alk shelf life question

How long can i store diy alkalinity solution (randy's 2 part).... how about 1 or 2 years. I found some remaining from my last tank..(mar 2019).... then i mixed that with new diy and seems ok.. Also what's the alk supposed to be in the solution directly when tested?..12 dkh? Thx

www.reef2reef.com

If you really wanted, I guess you could mix up a small thing of salt and do the math from one of the calculators and "dose" that, then re-test and see if your alk/ca come up as predicted. If so, should be good.