# Lily pipe outlet - placement r.e. waterline



## nry (9 Mar 2008)

I've found that unless I have my lily pipe outlet breaking the waterline significantly I still get a build up of surface scum (like that which hangs around lampposts at night but easier to get rid of) - moving it beneath the surface does give a vortex but this doesn't help much to clear the scum, barely touches it usually.

Is it usual to place the outlet above, beneath or on the waterline?  Mine are the PM 12mm pipes for reference.


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## ceg4048 (9 Mar 2008)

Hi,
     Try adding more nutrients and CO2. Then you won't have any noticeable surface scum to worry about. This won't help the lampost types though...

Cheers,


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## GreenNeedle (9 Mar 2008)

yeah I read it is to do with CO2 (although I think mine is to do with some very hungry Rams that demand bloodworm twice a day)

I have the Lily under the water most of the day and sometimes up at nightime if there is scum.

since I changed from Rhinox to Needlewheel the scum is a lot lot less so I assume it is defo CO2 related.

Andy


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## nry (9 Mar 2008)

I'm on 30ppm already, don't fancy notching it up any further, though I am looking to ditch the Jaqno, no more efficient than a Rhinox diffuser and a great deal more annoying when the filter gets a clean out.


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## GreenNeedle (9 Mar 2008)

I was on 30ppm according to the DC but now I have the maxijet pumping around and am still green but less scum maybe my circulation was not so great after all!!

Andy


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