Sump pumps are not really intended for pond use because of the relatively high running cost of the sump design.They are also not usually designed for continous running.
However the DRAPER range has proved to be extremely reliable with less than 95% failure rate and a competitive price for their quality. They are available with an automatic float switch to control their operation in "gully emptying mode" and all come equipped with a variable hose tail connection accomodating .75" to 1.5" hose.
THE DRAPER 120 gives 1000gph and a 3m head
THE DRAPER 120A has the automatic float switch for £5 .00 extra
Price: £70.00