On Apr 13, 8:41 am, ~ jan wrote:
On Fri, 13 Apr 2007 03:20:28 CST, "RG" wrote:
Aaah, what a pleasure to get rec.ponds again without the disturbed
commentary. Many thanks to those who pulled it off.
Our pond is 3 years old, 400 gallons, 30" deep, partly shady, 6
goldfish and 3 koi who are ~6" long. We're in San Francisco, moderate
weather.
Some perplexing new changes lately: 1) Fish seem scared. 2) String
algae has arrived.
1) In the last 3 weeks the fish have been hovering near the bottom,
seemingly scared. This was never the case; they'd always swim around
the top, especially during feeding. Now they won't come up at all.
Of course they could be terrified of the Great Blue Heron we saw on
the neighbor's roof 2 weeks ago (said bird then flew over to the
flimsy tree above the pond, though the bird never went down to the
pond as we watched). The heron could be visiting when nobody's
watching, but no fish are missing. It's a small, enclosed yard; I
doubt the heron's visiting that much. Could something else be the
problem? I water tested last week and everything's normal. Not only
do they hover near the bottom, I've seen them so low sometimes they've
got dirt/mud on their backs. Any ideas? Is this some weird spring
ritual? Or, is it related to...
2) String algae. We never had it before. Crystal clear water, in
fact. No big change in amount of sun. What causes this stuff. Maybe
I should leave it so baby fish & frogs can hide in it. Does it bother
fish? Can they get caught in it? Do they like it? Can I get a kind
of fish that eats it? I've got alot of elodea growing in there.
Thanks for any help.
If you've never had string algae before... it could be because you have
more nutrients, bigger fish now. 9 carp type fish in 400 gallons is quite a
bit of poo. ;-) What kind of filter do you have on there?
Since you've seen a heron, if you don't have something to prevent him from
flying down, very likely he's managed it. I'm not a net person, I use a
motion sprinkler, so far so good. Works on both heron & raccoons.www.contech.comto see a picture... you may find it cheaper by searching
the web. ~ jan
------------
Zone 7a, SE Washington State
Ponds:www.jjspond.us
Thanks everyone for the replies. Much appreciated.
I'll pass on the net idea. I have doubts about a sprinkler because
the pond, which is sort of a strangled-curved-kidney shape with many
plants around it, won't be 'served' by just one sprinkler. Also,
won't the sprinkler sprinkle me, and my cat and wife and daughter?
How does it discern? I'm not too worried about raccoons. I know
they've been at the pond since I put it up (seen pawprints, seen
them). I'm still not sure the frightened fish are caused by the heron
either, since we've seen a heron last year, and an egret the year
before that. I did add a new koi a month ago, shortly before the fear
behavior began. Could it be weird grouping psychology.
No, Jan, I never had string algae before. I have an Oase Filtoclear
800 pressurized filter with an Oase Aquamax 1000 pump (great pump;
only draws 9 watts). The filter has a handle/backflush system to
rinse out the gunked-up sponges inside. I've been backflushing it
every 2 weeks or so.
With alot of this string algae, is it possible to stop feeding the
fellows? (I've only been feeding them a tablespoon of tiny koi
pellets every 3 days or so.)
By the way, here's another oddity: I've got tadpoles in the pond that
have remained tadpoles for 3 years. Only one turned into a frog last
year.
--Rob