and another thing... talkative mood today...

okay, i`m ready to build my pond, its not going to be as big as i first
imagined, 3'*3'*6'...

Its going to be built in the shade of my garden shed, with an external
homemade filter built out of a water feature pump and an old fibreglass
storage tank filled with media but i`ve had acouple of ideas for water
changes...

Idea one is to fit a ballcock into the pond, attached to a hose connected to
the water supply so that it refills automatically whenever evaporation or me
bucketing out water to feed the garden causes the level to drop. the only
drawback to this is that i can`t dechlorinate the tapwater prior to adding
it to the pond. will this matter so much with the larger volume of the pond?

The second idea I had was to put a cistern in the shed with the top off it,
and a pipe running into the pond so that adding water is accomplished by
flushing, with excess pond water going into a water butt via an overflow. As
the cistern fills immediately and then sits for the next flush the chlorine
will just gas out of it... although theres only a couple of gallons in the
cistern, if done daily will this be enough?

I`m a fairly basic plumber but i can`t see any real problems with either
plan, anyone else done anything similar?

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