Alkalinity dosing question from a noob.

markysgirl · Nov 3, 2020

Good morning R2R.
I just read Randy's question posting thread so I will do my best.
Question
1. What is the best method (or what method did you use) to get alkalinity stable when beginning to dose alk for the first time?

History
I started my first tank in January 2020 and so far it is going well. Ups and downs but overall pretty well. My pre water change Alk was ~6.3 pretty consistently from the start so on September 1st I started adding BRS 2 part manually.
I did a bunch of research, decided on BRS two-part, watched the YT video, used the online calculator, and figured out what my daily dose is. I have been adding that daily dose by hand every day. My Alk goal is 8.5
I have continued to test weekly at first and now bi-weekly.
12 OCT Alk = 8.1
3 NOV Alk = 7.3
I would love some advice on what you think is going on here.
pH and Salinity have remained stable at 8.3 & 1.025 respectively.

I am sure some of you are wondering about Ca. My Ca was always 380ish before dosing the 2 part. I raised it to the BRS recommended 420 in September. Since then Ca has been, 7 SEP = 440, 20 SEP 410 (both of these were Salifert tests then I got a Hanna Checker) 3OCT = 426, 12 OCT = 465, 3 NOV 434. I have no idea what to think about this or how to deal with it. I have not added any Ca since the very first dose in September.

I also raised the Mg to 1300 and per the BRS instructions, I have not added anymore.

I would appreciate any advice from seasoned refers and welcome any further questions needed to clarify.

Randy Holmes-Farley · Nov 3, 2020

Your alk decline is very low, so you do not need much extra dosing.

I'd boost the alk by adding an extra 0.4 dKH three times over three days (to get to your target), then just just add an extra 0.1-0.2 dKH of the alk part (and equal amount of the calcium part) each day going forward and monitor that for a while.

The calcium variation is just noise in testing.