Gravel Vac question

So maybe a stupid question, but i've heard conflicting ideas on cleaning gravel. I've heard some people say not to clean too deep down into the gravel, but i've heard also that you should clean all the way down. Any insight?

 

Saltwater: Don't clean your sand. Maybe use a chopstick to stir up some of the detritus in it. Clean crushed coral well.

Freshwater: Vacuum the gravel completely, top to bottom, do 1/2 the tank (like do the left side, then the right side, then the left) per cleaning.

 

I don't clean my sand at all. I have critters that do this for me. But if you think you should clean deep I would suggest only doing a small area in a different spot each time so you don't reduce your nitrifying bacteria population to badly.

 

if you have a deep sand bed thats de nitrifying then dont. If not then yes you can. If you never have done it before i would do little at a time not all at once.

 

Alright thanks guys. I haven't been cleaning it because thats what i thought... I've had my tank set up for about 8 months now and haven't had any problems but i just thought i should check. Thanks!