Question
I am trying to raise the PH, Hardness and alalinity in my 1800 fish pond quickly.  I have lost 10 of 12 Koi and 6 of 12 goldfish in 24 hours. I was told by a local petshop that I could use 30lbs of crushed coral. Should I also add any baking soda also & how much.

Answer
Hey Terri I never mess with my water because if the pond is set up right you never have to.The rule of thumb is 2 to 5 gallon per fish maybe more depending on the size of the fish. What happens is the carbon dioxide that the fish leave in the water creates an acidifying affect. If you have the right amount of plants in your garden pond they will eat up the carbon dioxide and make the water less acidifying. I never touch my pond except to clean it out. Once it is in balance you shouldn't have to do much. Thanks Eric