NANFA-- wintering fish
Wed, 31 Dec 2003 17:15:50 EST

I wrote about overwintering my fish a month or so ago and didn't see it on
the elist, so I'm betting forgetful me closed my post without sending it. So,
I'll try again. I have a couple dozen YOY dollar sunfish, a couple dozen
YOYpumpkinseed sunfish, about 50 YOY pygmy sunfish, about 100 YOY tadpole madtoms
and about 50 YOY golden topminnows that I keep in a building that has remained
between 42-50F this winter. I also have similar numbers of the same kind of
YOY fish I keep in aquariums in the daylight basement of my house where the
temps remain 60-68F.

I feed live foods only. I've been fortunate in finding quite a few midge
larvae, glass worms and daphnia so far this winter along with a few small mayfly
nymphs; pretty much on a weekly basis. The fish in my warmer setting
[daylight basement] eat just as though it's summer - they will eat daily if I can
collect enough live food. Because this isn't the case most weeks, they are
exceedingly fat the day of feeding and usually somewhat fat-looking the day after I
feed, but start looking gaunt after that time. The only exception being the
madtoms, as they almost always look a little "chubby". I suspect they munch on
the small snails and plants available to them on a continuous basis. For as
much food as they consume, these YOY fish don't appear to be growing near as
fast as they did in the summer. Maybe the temps still aren't optimum warm?

Now, about overwintering the other YOY fish in the cold setting [42-50F].
The dollars, pumpkinseeds, pygmy sunfish and tadpole madtoms all eat at these
lower temps. Fact is, I don't notice any difference with the amount of activity
and eating by the tadpole madtoms from those in the warm setting. However,
the sunfish & pygmy sunfish seem to have some daphnia or a few glass worms or
midge larvae left in their tanks all week long and I don't feed them nearly as
many to start with. But, they all always look kinda "chubby" like they're
doing really well and are getting as much to eat as they'd like. None of these
fish look gaunt in the middle of the week like the sunfish in the warmer
setting do and although these fish also aren't as active as the fish in the warmer
setting, they are still actively feeding, albeit sporadically. These fish do
not appear to be growing, inspite of their robust appearance.

The exception on the YOY fish in the colder winter setting are the golden
topminnows. These fish seldom eat, fact is, I've only observed them eating on a
couple of ocassions since early November. These fish vary in their appearance
from nearly gaunt looking to relatively robust and summertime normal looking.
I do have daphnia in with them at all times and the daphnia population
diminishes after a couple of weeks, so I'm guessing either the daphnia start to die
off or some of the topminnows are eating. Just not enthusiastically and not
all of the fish are consistently participating.

The fish in the colder setting are easier to care for, espeically because
they don't eat as much, but also because I haven't had to have aerators or
filters in their tanks. I keep snails in all of my tanks as well as plants, so that
also helps. I'm probably at the halfway point of my overwintering and I've
only lost a couple of the golden topminnows, so I'm guessing everything will
come thru the winter in pretty good shape.

Does anyone else on this list have overwintering experiences in observable
colder settings? This is the first time I've overwintered so many fish and
especially so many YOY fish and I'm happy with the results -- so far.

Bruce Scott
Meridian, Idaho
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