Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Just looking at the MSDS for the alkaline buffer and sodium bicarbonate I am not sure there is a difference.
Perhaps the short life of baking soda in the tank is because whatever removed the carbonates from the tap water is still working? Certain substrate, nitrifying bacteria and plants can all remove the carbonates no matter if they came in with the water or were dosed afterwards from a jar on the pet store shelf or an orange box in the kitchen. Test kits for aquarium use are not very accurate, so seeing falling levels, then 'suddenly' zero might not really mean much.
Run this test:
Get 3 jars or glasses of tap water.
Add the same dose of baking soda and alkaline buffer to each of 2, the 3rd is plain water, no additives. Measure carefully, by weight if possible.
Test GH, KH, pH and TDS when you first set it up, then daily for several days.
Stir the water once in a while, or else set up the same system them, such as splitting a small air pump between them. Make sure the water movement is the same. Easier, perhaps, just to stir them with a spoon morning and evening.
a) they create the same initial change in the water parameters compared to the plain water.
b) maintain that change the same length of time.
I have used baking soda in several tanks for several reasons and had no problem with it maintaining the KH level.
If SOMETHING was removing the carbonates before I added the baking soda, then that same process continues and removes the carbonates dosed via the orange box from the kitchen.
If NOTHING was removing the carbonates, and I just wanted harder water (for Rift Lake Tanks, or Live Bearers) then that same nothing continues doing NOTHING when the baking soda is in the water, and the water maintains the proper level of KH as long as I have let the tank go. Mostly I was doing weekly water changes, and setting up the new water with baking soda to the parameters I wanted in that tank.
In some of these tanks I also had coral sand, either as substrate, or in the filter. These tanks also stayed stable through the week, but the reaction was too slow for me to add tap water to the tank for a water change. I would add baking soda to the tap water so it would be where the fish were used to it. I was doing large water changes, so that much drop would not have been good for them.
Why is Sodium bicarbonate a 'chemical' (with undesirable overtones) and baking soda is OK?