Buffers refer to the KH# in your water. The higher the KH (more buffered) the higher the
pH will be.
When water buffered with KH of around 5 dh (degree of hardness), the pH is more stable and won't raise or lower quickly or easily, known as pH swing.
The higher the KH is over 5 or 6 dh, the higher the pH will become but will
usually level out around pH 8.3 after KH gets over 8 or 10 dh.
However, quite often folks do very well with fish breeding etc. in the water available to them.
IMO, if your fish are tank raised and doing fine in your water, I wouldn't fuss too much with that type of adjustment to obtain "perfect" water.
To me, perfect water is obtained with a regular routine of the partial water changes keeping the water stable and
having 0
ammonia, 0 nitrItes and low (<20) nitrAtes.

hth,
alicem