Test the pool water with a reliable test kit
Check the current total alkalinity level
Use sodium bicarbonate to raise alkalinity
Calculate the required amount based on pool volume and current level
Dissolve the sodium bicarbonate in a bucket of pool water if needed
Add the solution slowly around the deep end or along the pool perimeter
Run the pool pump to circulate the water
Retest the water after several hours or the next day
Repeat in small increments if needed
Avoid adding too much at once
Keep pH within the proper range after adjusting alkalinity