The SeaClone is a bad skimmer, but a couple of mods can turn it into a decent skimmer at best.
I have seen people mention some sort of valve mod, doing away with the venturi, but I didn't pay close attention. You can cut the riser tube, but you need to be careful when you attempt that.
When had my SeaClone, I did the bioball mod and airstone mod, and both improved performance.
As for some links:
http://www.reefcentral.com/diy/seacl...ifications.htm
http://archive.reefcentral.com/forum...t=seaclone+mod
HTH