Question about Sodium Hydroxide

Reefen · Mar 12, 2023

I was not getting enough PH or coral growth with soda ash, so I put a co2 scrubber on and it is working, but then found Randys recipe for using sodium hydroxide for alk and ph saying there is more of a ph boost, so this may turn out to be more cost effective, will the sodium hydroxide still give me more ph boost if I have co2 in my tank

Randy Holmes-Farley · Mar 12, 2023

All tanks have CO2, and consuming CO2 is how all high pH alk additives raise pH. Hydroxide consumes twice as much Co2 as carbonate per unit of alk added.

cdklos · Apr 20, 2023

Reefen said:
I was not getting enough PH or coral growth with soda ash, so I put a co2 scrubber on and it is working, but then found Randys recipe for using sodium hydroxide for alk and ph saying there is more of a ph boost, so this may turn out to be more cost effective, will the sodium hydroxide still give me more ph boost if I have co2 in my tank

I have been using sodium hydroxide for a while now. I have a special setup, but the idea is the same. I have a whole home RO system that feeds my entire house, including my fresh water top off and my salt water mixing station. Using a peristaltic pump wired to my RO, any time my RO runs the pump runs and injects sodium hydroxide to my water. The pH of my water runs about 9.5, so every time I mix new salt water or my ATO comes on, it's pumping high pH water into my system. The CO2 level in my tank room is about 550 on average, and my tank pH maintains about 8.5. I purchased the 5 gallon jug of sodium hydroxide from a local water treatment company for $250.00. Feeding my whole house and tank, should still last me about a year or more.

reef_ranch · Apr 24, 2023

cdklos said:
I have been using sodium hydroxide for a while now. I have a special setup, but the idea is the same. I have a whole home RO system that feeds my entire house, including my fresh water top off and my salt water mixing station. Using a peristaltic pump wired to my RO, any time my RO runs the pump runs and injects sodium hydroxide to my water. The pH of my water runs about 9.5, so every time I mix new salt water or my ATO comes on, it's pumping high pH water into my system. The CO2 level in my tank room is about 550 on average, and my tank pH maintains about 8.5. I purchased the 5 gallon jug of sodium hydroxide from a local water treatment company for $250.00. Feeding my whole house and tank, should still last me about a year or more.

This I need to learn more about. What is the alk of your RO water after injecting the sodium hydroxide? What are your alk and calcium level in the tank and how do you maintain them?

Randy Holmes-Farley · Apr 24, 2023

reef_ranch said:
This I need to learn more about. What is the alk of your RO water after injecting the sodium hydroxide? What are your alk and calcium level in the tank and how do you maintain them?

FWIW, the alk of my DIY two part recipe using sodium hydroxide is exactly the same as the alk of the sodium carbonate/soda ash recipe: 5300 dKH. I don't recommend adding sodium hydroxide except as needed for alkalinity.

Second New DIY Two Part Recipe with Higher pH Boost

In a previous thread, I posted a true two part DIY recipe: https://www.reef2reef.com/threads/new-diy-two-part-recipes-with-higher-ph-boost.344500/ But some folks may want to just swap the new ingredient into my 2/3 part recipe (as used by BRS, for example). Here's the original recipe link...

www.reef2reef.com

reef_ranch · Apr 24, 2023

Thanks Randy, I am using your high pH two part. It works great. I was curious how he manages his dosing when he uses sodium hydroxide in his RO water.