Trouble keeping pond plants alive

[Reflections]

OK thanks. No cement in our pond at all, rubber pond liner, natural spring water is our water source, we use in home to, but I've noticed that all our tapware does get a build up of calcium I'm guessing, as it's hard a white when dry, anywhere the water regularly runs or touches, ie. Around shower head and taps. Could this be source of high ph. And to be honest, that 8.8 is probably the lowest it's been. I've had readings of 9.5, my local pet shop told me to do 1/3 water change, which I did and yesterday when I took the reading we had just had alot of rain, which topped pond up to over flowing, so perhaps that's why it was lower reading. How do I get ph down and stay down? Thanks again

 

[addy1]

Do a test on your spring water, hardness, ph etc. I have the opposite issue, very acidic, very soft well water. I had to buffer everything up.

 

[Marck]

Take multiple pH readings. Most ponds have daily fluctuations in pH due to the amount of CO2 in the water during the day versus the night. This is due to photosynthesis by plants and algae lowering CO2 during the day vs. relatively constant respiration by all organisms raising CO2 at night. Due to this daily fluctuation most aquatic organisms can tolerate a range of pH values as long as the change is not too sudden or too extreme.