i had the skimz sk181 and loved it. i didn't have a huge bioload but it pulled out some nasty stuff. it was my first true skimmer and wish i never sold it with the 150 i had. i had a friend who bought a sk201 and he said the same thing. i will say the only thing is that aquacave is the only retailer for them so if anything breaks you have to buy from them. of course that is if it breaks