Ideally, it should generate a bit of skimmate every day (1/2 cup to a cup a day) from your tank.
Ed[/QB]<hr></blockquote>
1/2 a cup to a cup? Sounds like your overfeeding...lol Mine skims a gallon a month with 0 Amonia, 0 Nitrite , and 0 Nitrate. With a CC substrate!!