top up and ph

[Quagmire]

If its small amounts of top off at any one time,it wont change your PH.Larger top offs you might want to use a PH buffer.I get 2 1/2 gal a day evaporation this time of year without my sump fan running and dont worry about PH.But if I forget and have to add 5g I'll buffer it. Thats on a 60-70g total system.In the Summer when my fans are going I use buffer due to the larger amount I have to add.