If you do a web search you should find some info on mods.
If you want to do a low cost, and not destroy your skimmer, you can use it as is and add some black filter foam to the overflow. This will cause the level to rise in the collection tube and you should get more junk out.
For about $8.00 you could add a 1/4" ball valve to the air line, this replaces the original and is supposed to give greater air control. While your at it I would get some neopreane air tubing, as the plastic original will clog with salt and harden, thereby restricting airflow.
If you want to cut off the innermost tube and leave about 2 inches it is supposed to increase the dwell time of the air/water mix. I used a stainless steel wire suported with two wooden dowel rods, heated up the wire and hot cut the tube inside the skimmer. It will take a few tries but you will get it.
My seaclone is only used now on my quarentine tank. I have a Reef Concepts skimmer that is a foam monster and is probobly the best you can get ( $550.00). If I had to do all over again I would have paid the cash up front. It does make a big difference in how clean the tank stays, and how stable the water parameters are.