Change out my sand?

I think the recommendations against fall into two categories. 1) if it's a deep sand bed (3-6") it can stir up an acid that can build up in the deep areas. 2) it can take off the aerobic bacteria on the surface of the sand. I'm about to try vacuuming the sand myself so as of now, I have no opinion either way.

 

Type/brand doesn't really matter. You'll want one with a small hose, though; that will reduce the suction and make it easier to control so you don't vacuum out all of your sand.

 

This was going to be my recommendation. I bought one which is recommended for like a 20g tank and use it on my 55g. It is slow enough that I can vacuum all my sand that i can reach and only take out 5 gallons, which is what i normally change out every week. It takes a bit of time but that was what I was going for when i bought that size. I do recommend you look for one with a hose clip for the bucket, and possibly a priming bulb to start the siphon. I didn't think about the primer until i opened the box.