On Jun 8, 6:05 am, "fpbear" wrote:
Mosquitofish are taking care of a large pool at my mother's house in
Southern California (which she couldn't maintain anymore), and we are
thinking about putting a pool cover on a portion of it. Would the
mosquitofish still survive if we cover 90% of the pool? We would leave a
section open, of course, so that they could still feed a little bit.
Although I'm not sure if the cover would make the water too warm or deprive
the water with not enough sunlight or larvae food to sustain the fish?

Covering the pond is going to cause you much more work than not
covering it. It needs plants. Invest in the purchase of some water
hyacinths, water lotus or waterlilies. Does the pond not have plants
in it? They really are not that costly and in California you will not
have to worry about losing them to freeze - actually what part of
Southern California? Covering is going to cause die off of what is in
there which will kill the fish - you will then have a nice home for
mosquitoes. Since you don't have large fish in it, the pond should
take very little maintenance. The more shaded it is the less problem
you will have with algae. Plants in the pond count as shade. If you
have one of those store bought filters with a pad that needs cleaned
every week get rid of it. Put the water pump in a five gallon bucket,
fill it with lava rock and rinse the bucket out with pond water once a
year. You can cover the pond with a black netting used to protect
fruit from birds. This will keep out the leaves, shade it a bit but
keep it alive. That is the critical word here - alive. I assume
someone is spending time with your mother at least once a week. I
also assume this pond is something she is fond of and that gives her
pleasure. Very little research on your or their part should make it
easy to keep this pond alive for her pleasure. I lost my mother this
year. I would do anything if I could give her one more day of
pleasure with her garden.