Appreciate anyone's insight on what may be going on with my pond...
We're in middle TN, with a dug pond of about 1/10 acre. 6.5' at deepest point. Dug about a year ago, currently has toadpoles, bullfrog tadpoles, frogs, and salamanders living in it (they've been in it for the past year). pH tested with (understood to not be the most accurate) pool test strips measures consistently around 6.8.
About a week and a half ago we stocked with ~2lb FHM and have had them dying off since (maybe 8-10 a day), followed by what looks like a pretty big die-off over the weekend. I expect some to die after transport, but these aren't just the scrawny/weak-looking ones.
We stocked last spring as well, shortly after digging the pond, and had the same issue. I wrote it off to being "too early". But at this point everything is well established, and the amphibians seem to be doing really well.
Any guesses as to what's going on, or what I can test to figure it out? If it were an oxygen issue I would think the tadpoles and salamanders would have issues also (granted, over the past month I've seen two dead bullfrog tadpoles and two dead salamanders in the water). Our house is being built about 100' from the pond, but the slope of the land shouldn't allow runoff from the build site to the pond.
Is your FHM supplier the same for both cases? I'd get a box of medium FHM from Anderson fish farms and see if the same occurs ..unless you have another supplier you can get 2-3lbs from, close by. I might be wrong but the mortality you are seeing sounds more like stress than water quality.
If it were me, I would change suppliers of your fish. They apparently do not have qualms of selling less than healthy fish to naïve customers. This assumes that you after purchase that you handled and tempered the fish properly upon introduction to the pond.
