I have been thinking on this and have even talked to the guy at my LFS..We do all of these things to get the PH to a certain level, add salt, maker sure the water isn't too soft or too hard..But is it too much?..Most LFS, or bigger pet stores don't adjust every little water imbalance in their tanks..And I have even talked to several that have said, that the fish are accustomed to how the water is at the place of purchase and changing their environment drastically could be even worse on the fish...My LFS does water changes to keep ammonia down and tests his water every couple of days..But doesn't worry much about the PH of the water and hisa fish are healthy..Do we get over cautious and do things that aren't necessary?...I was told that 25% water changes should be done every other day..I started testing my water and don't have to do water changes but every other week..I have 1 platy, 2 dalmation mollies 2 mystery snails and 3 pin fish(forget the exact name) and a crab in a 10 gal tank..All of my fish are active and seem happy...Anyways..Just throwing this out there for other folks opinions.