"Ken Kose" wrote ...

"Bob Hobden" wrote:
"Ken Kose" wrote

Had a freak hail storm on Saturday in Chicago. There was about a1/2
inch of hail (1/4in size) on my deck. The size of the pond is
10'x4'x3'D. I lost 7 goldfish (about 7" in length). What happened? Did
the hail cool the water too quickly? This never happened before.

Probably thermal shock as you suggest, but a few questions for you...
1. Were they the biggest fish in the pond?
2. Was it hot and sultry, humid?
3. Have you got lots of plants in the pond, especially oxygenating
plants.

-- Regards
Bob Hobden
W.of London. UK

Hi Bob,

1) Yes, they were the bigger fish that went belly up.
2) It WAS a warm day ~85F and humid with 90-95F the past week, so
water temp was probably higher than normal.
3) Yes, lily pads and water hyacinth, about 90% coverage on the
surface plus an air stone.

Just trying to figure this one out. Was it shock, or did they think it
was food as the other poster noted and got beat with the hail pellets?

Thanks for your comments,


Something that happens over here occasionally is that in warm humid nights,
summer thunder storms at night for example, the water cannot take up enough
oxygen to compensate for the carbon dioxide put out by the plants as they do
at night and the largest fish suffocate. Even with an airstone if you couple
that lack of oxygen with a severe sudden thermal shock the large fish will
have a problem.
Over here the "experts" are always telling people to put more oxygenating
plants in their ponds but it can lead to sudden deaths during hot humid
nights.

-- Regards
Bob Hobden
W.of London. UK