Ph changes a lot and quickly (hourly) while alkalinity changes very slowly (mths). If the alkalinity is 25 you could use a little lime. See this


SRAC 0464 Interactions of pH, Carbon Dioxide, Alkalinity
and Hardness in Fish Ponds

http://srac.tamu.edu/tmppdfs/3766418-464...a661f7d1e435728

http://srac.tamu.edu/getfile.cfm?pubid=112



Last edited by ewest; 03/09/10 09:07 PM.