You should probably decide on an acceptable range of water levels in the
pond. Depending on what flora and fauna are chosen to populate your pond,
that range will vary. Some plants, irises and lilies come to mind, are
quite tolerant of fluctuating water levels. Others are not.

For example, my pond is set up so that it can safely overflow, so obviously
that is the maximum water level. I have my pump on a shelf about 10 cm
below the top of the pond, so when the water level goes down 10 cm the pump
stops working. That's a safety precaution so that if there is a leak the
pump doesn't empty the entire pond. Also when the water gets down to where
the pump stops working, I simply refill the pond with tap water.

Rich

"R L Tosswill" wrote in message
...
The recent spell of summery weather in the UK has caused us to wonder how
necessary it is to replace
water lost by evaporation in our newly-created garden pond. Our small pond
has a surface area of
about 6.5sq.m and a maximum depth of about 80cm. No fish, usual plants,
currently quite healthy.
What effect can we expect to see from water loss if it progresses? So far
we have lost about 4cm.
Richard