View Full Version : Ugj?

12-20-2005, 10:28 PM
Can any one explain to me how these UGJ's work? and what the advantages and disadvantages over other filtration systems they have?

12-20-2005, 11:24 PM
what they do is circulate the water from the bottom up. People Love em because it keeps the fish crap off the sand or gravel and can be better filtered through whatever system they are using. I am curious about the effect of makig more surface area for the air to dissolve into the water (which is what the hets are normally used for).