Question
we set up a 700 gallong horse trough for a pond..its been running for over a week..running a pondmaster 1500 filter system.

..put some Big goldfish in(from a local Fish store)..so far there living OK..few have died..my PH is fine..alkalinity is very low though..what can i do to bring our alkalinity up in the pond?

im thinking the alkalinity maybe our predator...

Jen

Answer
To bring up the alkalinity, add some sodium bicarbonate (sold as baking soda).  If a predator got your fish, you'd either find no bodies, or they would be torn up.  Did you find the dead goldfish?  My pond has very low alkalinity; I add some baking soda.  My fish don't seem to mind the low alkalinity.  

Larger fish are less able to adapt to a new home so you may have more luck adding smaller goldfish.
Good luck!

Robyn
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