Raising alkalinity

[Missjmeide]

How can I raise the alkalinity and pH in my sw tank?

 

[Fishkeeper26]

Crushed aragonite will naturally raise it

 

[mr_X]

agitation at the water surface does a good job raising ph. just aim a power head towards the surface to make it somewhat turbulent.
baking soda raises alk.

 

[Missjmeide]

How much baking soda should I put?

 

[mr_X]

from this article-
Chemistry And The Aquarium: Solving Calcium And Alkalinity Problems — Advanced Aquarist's Online Magazine


"In gauging how much to add, here are some rough guidelines:
Baking SodaTo raise 50 gallons of tank water by 1 meq/L will require about 16 grams of baking soda (sodium bicarbonate; sodium hydrogencarbonate). Since a level teaspoon of baking soda weighs just under 6 grams, then 1 teaspoon will raise the alkalinity in that 50 gallons by ~0.4 meq/L (~1 dKH).Washing SodaTo raise 50 gallons of tank water by 1 meq/L will require 10 grams of washing soda (sodium carbonate). Since a level teaspoon of washing soda weighs just over 6 grams, then 1 teaspoon will raise the alkalinity in that 50 gallons by ~0.6 meq/L (~1.7 dKH)."please read the entire article. why is your alk low? did you add calcium? in most cases water changes will correct any parameter problems. water changes will also replace calcium and alk, and other necessary elements, as well as remove waste.

 

[mr_X]

and this info seems helpful as well-

There is absolutely no advantage to keeping calcium anything over 420. Higher calcium doesn't make corals grow faster so if your at 450 no worries there. If you use a salt that is high in ca to begin with you may only need to dose alk. You can simply use Arm&Hammer baking soda. I've been using it for years.
This article may seem a little complicated, but it's really not.
An Improved Do-it-Yourself Two-Part Calcium and Alkalinity Supplement System by Randy Holmes-Farley - Reefkeeping.com
Basically you want to use Recipe 1 for alk. Bake 2 1/4 cups of Arm&Hammer baking soda in the oven at 350 for 1 hr. Get a 1 gal milk jug, fill it about 3/4 of the way with RO/DI water and add the baking soda. After it's added, top off the jug with RO/DI water. You now have 1 gal of alk supplement.
The only way to know how much you will need to add is test today, test tomorrow, the day after, and the day after again. See how much your alk drops each day, or every 2 days, etc. If it drops 1 dKH every 2 days you can dose the equivalent of .5 dKH every day....if you want to dose every day. How ever often you decide to dose you should never raise it more than 1 dKH per day.
Use this calculator ('Reef Chemistry Calculator FV') to figure out how much you need to dose. Enter your total water volume, your current dKH and what you want it to be, then for the supplement pick Randy's Recipe 1.
For example, if you have 125g total water volume, your alk is 6 and you want it to be 7, you need to dose 3 fl oz of supplement.

And don't foget about mag. If your corals are using ca and alk, they are also using mag.

 

[Missjmeide]

Thank you this has been a big help.