I started two half-barrels in the spring as an addition to the regular pond. They were both doing great until recently. A few months ago one started having problems. Many of the plants died or were shrinking. I thought maybe it was the cooling weather but we've had a warm couple of weeks now with no recovery (when I say "cooling", I mean nights in the 50s with a few in the upper 30s/lower 40s.)
Today I got in there and cleaned it out to have a look at things. I found a lot of mosquito fish, all doing fine, and many snails, most of them dead. I also found lots of weird-looking insects buried in the smutz at the bottom of the half-barrel. Alive and gross-looking. There was lots of dead string algae floating.
I cleaned out the smutz, tested the water, and all levels were in the "acceptable" or "ideal" range. I don't know what the problem might be! I went ahead and moved most of the fish to the big pond just in case it was overstocked. But like I said, they were mosquito fish, mostly juveniles. I also added more plants to replace the dead ones. In the pond are cattails, pickerell plant, water hyacinth and water lettuce. It formerly had anacharis but all that was dead, so I added a little more.
Any thoughts about this?
