Baking soda question

[DJRansome]

KH does not need to be 8 to buffer. KH=4 will buffer fine.

Determine how much to add for each water change and you should be fine.

I have had aragonite substrate and crushed coral in my filters for 10 years and pH=7.8 has not increased at all between tank and tap...my KH and GH are 7 both tank and tap.

 

[brianf40]

This site is so much better than the other site i belong to.... You guys actually reply.... When i top my tank off due to evaporation do i use my buffered water or just plain tap water. I guess im wondering if baking soda stays in the water after evaporation?

 

[DJRansome]

Better not to top off the tank at all, it will mess up your chemistry. If you keep it covered, it will stay full enough to last one week at which time it is ready for PWC anyway.

 

[brianf40]

good point

 

[duanes]

The buffering capacity of baking soda (for simplicity sake, calcium bicarbonate) is converted to other compounds as it is broken down by the acids of metabolism. Fish are constantly producing uric acid (urine) from their gills (24/7), this is what lowers pH, along with all the other metabolic processes in the tank, and filters by bacteria etc etc.
You do water changes to keep the tank water from acidic, and baking soda helps to keep the tank from becoming a toilet a little more quickly.
But by doing water changes you are actually removing uric acid, and adding new water with all those buffering abilities.
It is the acids that build up, when only topping off a tank, instead of doing a water change