Salt and ro water


New member
Not sure if this is the right place to post this. Im sorry if its not.
Can anyone tell me if there getting the same problem as me.
I use TMC pro reef salt. I have for a long time, Ive always used RO water. I bought a new ro system 4 stage with deionisation stage. The last 2 buckets ive had ive had problems with. This is how i get ready me water for a water change. I fill the buckets 2x25l then add pro reef i then run a 1200 header pumps in both buckets with air pipes so the water is getting loads of air from the headers, i leave the water for 72 hours before i use it. I then test the water for SG, nitrate, phospate,PH and Kh. Ok the problem i have is the PH is 7.8 and kh is 5dkh. I started adding TMC reminral which bought the PH upto 8.0 and 6dkh. I then have to add a buffer to bring the ph upto 8.2 and 12dkh. Basiclly im trying to find a salt which i do not have to use super buffer and TMC reminral. I thought that was what pro reef was for so you didnt have to use buffers and reminralizers. Iam i silly to think this. And any suggestions i would be very thankful for.


Randy Holmes-Farley

Reef Chemist
Premium Member
I do not know what the alkalinity normally is in that mix, but I'd boost the alkalinity with baking soda. Cheap and easy. This calculator show show much to use:

Reef Chemicals Calculator

The pH is driven by the alkalinity and the CO2 in your home air. More fresh air would raise the pH, and do so even more after boosting the alkalinity. You could also bake the baking soda first to give it a pH raising effect. This article has more:

Low pH: Causes and Cures


New member
I have tested alkalinity on TM-pro that ranks from 6.5 to 7.5 dKh, it usually needs some alkalinity supplement.