well, i'm just a beginner in this whit saltwater. there are two types of skimmers 1. venturi: mixing the water with air in an electrical engine. then the mixed water and air goes in to a pipe/container called reaction chamber. the bubbles goes up and take the dirt up to the surface where it createing skim. 2. oxygen stone: same as no 1. but ther is no engin. an airpump is connected ton the oxygenstone witch releasees the bubbles. this type of skimmer aint such effective like no 1, but is cheap to boy. require that yuo replasing the oxygenstone a copple of times per year. in the raction chamber the air takes the dirt to the surface and the cleaned water goes down to the bottom where the the water is taken out of the chaimber. If You notice any strange spelling, I aint good in english. regard claes. Tak ska ni ha fr hjelPING!! <a href='http://www.smileycentral.com/?partner=ZSzeb008_ZCfox000' target='_blank'><img src='http://smileys.smileycentral.com/cat/F/0/161.gif' alt='Thank You!' border=0></a> is it worth it? (förlott.. jag prova att pråta svenska och lovadmig att jag ska INTE prta engelska.. men det funkar inte SOME TIMES..) <a href='http://www.smileycentral.com/?partner=ZSzeb008_ZCfox000' target='_blank'><img src='http://smileys.smileycentral.com/cat/16/16_5_1.gif' alt='Fish' border=0></a> Är det lät at byga egens skumare?