Have got several pond plants growing in an old washing up bowl ready to
be put in the pond but I want ensure that the water is safe for them
first. I put some in last year and they died within a few weeks.

Anyone got any advice as to what I can do to try and clean up the water
a bit? Any help or advice would be very much appreciated.

Your up-flow filter will work as long as your fish load is not too high as
compared to your water volume in the pond - but - a brand new filter takes
from 3 to 4 wks to work biologically (can't seem to get the sp right ! ) as
the media is new - it comes on-line quicker after the initial start-up -
trusting your filter is large enough, it will work - you need patience (for
another wk or so) and you will getr up one morn and see the bottom (just
like magic is the way I felt :~)))))))))))))))))))))) )
Gale :~)