From a purely layman understanding, if you arent experiencing big swings in PH, I'm not sure adding more lime will benefit you much. 7.2 is optimal, but if you do multiple checks throughout the day and find it is climbing into the high 8s or 9s, then lime would be beneficial to buffer those swings.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!