Peter Pan wrote:
I was wondering how often should I back flush my 3200 gal pond? And when
doing so, how much water should I take out.

Our pond is now attached to the overflow of a water butt. When it rains
the pond is topped up with rain water and the excess passes through a
pipe into an underground soak-away. I've no idea at what rate the water
is being changed, the fish seem happy though. After about 1 month of
British summer weather (plenty of rain) there has been no change to the
ponds pH, which was my only concern.

Another water question: I know ponds are not usually clear like a fish
tank. My last pond was a plastic insert and the water was fairly clear.
Now that I have a liner, it's no where near clear; its murky at best..
Any suggestions?

I use filter wool for the final polishing step. In the past I may have
incorrectly called it nylon wool in this group, it's also advertised as
polywool so I guess it's polythene instead.

Anyway, pass the water through it, change or clean the wool every few
days, and continue until water is sparkly and clear. I need to redo out
pond soon. The last water polish was about two months ago and it's now
looking slightly less than perfect. Some people might include the wool
in there permanent filtration setup, but I find it clogs too easily and
causes overflows.
Here is some from a UK eBay shop
http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=160261036136

Good luck with that.
David