4. Draining and refilling, is just going to give the algae a nice new batch
of water to work in and probably stress everything else. I wouldn't do it.

I think this one is a total myth, more a YMMV.

Every year I have to totally drain my lily pond to get the baby fish and
muck out. So all new (treated) water goes in. That was a week ago, still
perfectly clear. Course I started the filter prior to the clean out so
there would be some bio-bugs in it. I gently rinse the sides, but leave the
fuzz algae attached.... and the clincher, there are no fish in the pond,
just the frogs doing their thing (which feeds the bacteria in the filter).

Now sometimes I have gotten Suspended Algae in this pond, but it had
nothing to do with the new water, it happened later in the summer when the
pH went sky high. 9.0+ and I'd over harvested some string algae (at the
time I didn't have much fuzz algae). The lily pads were thick, but once
that pH goes over 9.0 it becomes very difficult for the higher plants to
remove the nutrients. I'm hoping this year the fuzz algae has a good hold,
so far it is looking good. I also added a pound of baking soda from the
start. ~ jan


See my ponds and filter design:
http://users.owt.com/jjspond/

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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