"Lostin1999" wrote in message
...

"SkyCatcher" wrote in message
...
Hi,

I have a 12000L pond with plants & NO fish. The filter/pump/UV are
appropriately sized & I changed the UV bulb 2 week ago - AND the pond if
still filled with green gloopy algae.

What more can I do to sort this out?

Help!



where is your pump in relation to filter outlet?

it is in the same side as the return fromthe filter - perhaps I need tomove
it to the furtherest away point?


how is your pond fed? is it a liner or natural?

its a closed system which & is sealed concrete


is it string algae (blanket weed to UKers)?

well I've never seen blanket weed so I don't know. Its clumpy and goey!


how fast are you pumping it through the UV?

according to the pump it would be at about 4500l/h at the height the filter
is at.


where is the UV in relationship to pump and filter?

the UV is attached to the filter - it is a heissner unit (filter & UV)


how much sun does your pond get?

it is in full sun (not hat we get much here in the North of the UK)!


for an approx 3000 gallon pond, id expect it to take longer than 2 weeks
to
clear.. also might be worth slowing down the flow through the UV..

I expected a few weeks but it seems to be getting worse!


if its string algae (blanket weed) it will NOT be affected by the UV or
the
Filter (it could however block your pump's impellor)

the flow seems to be the same from the pump but I'll check the impellor


how old is the pond? how long has it been "green slop"?

I inherited the pond with the house about 3 months ago & it has always been
green but it is getting worse!


recommend shading it a bit if in full sun.. and maybe introducing duck
weed
(and many other floating plants...) to starve the algae of light and use
up
some of the nutrients the algae is feeding off..

I've added marginals & floaters & lilys to help with this


really need a LOT more info to really offer help...

BTW what GPH (LPH) is the pump?

it is a Lotus 7500

what Bio filter media are you using? bio balls (the knobly oplastic type)

what
wattage is the UV? 18W



TIA

Lost



thanks for your help...