Well I just finnished vacumming my gravel on my 1850g and it took me just over three hours, nothing new ,I just thought I would share that with everyone. Just out of curiosity how long does it take to vac your gravel in your tank or tanks? All up it took me about 5 hours to do all of my tanks, I normaly do them on seperate days but today I was extraodinarily bored . :coffee: