Vacuum.

[the egregious]

Believe it or not I have just purchased my first tank vac and I have a quick question. Is it supposed to completely suck all of the sand out of the bottom. It says it has a way of separating the sand and the gunk, but, for me all it does it suck everything out.

 

[the egregious]

 

[dsbdude]

Substrate vacuums are usually used for coarse grains like crushed coral. I suppose you have sand and that is why your vacuum is sucking everything up. If you want to get gunk out of your sand bed, i'd suggest stirring the gunk up into the middle of the tank and them vacuum it from there. Keep in mind if you get good flow on your sand bed, you will rarely OR never have to vacuum. Hope this helps!