5 year old tank questions

[svpbeast]

I have a 65g hex tank with 10g sump. It has about 80 or so pounds of live rock and a 3" dsb.

2 clowns
1 coral beauty
1 lawnmower blenny
1 clown goby
1 fridmani "sp"

Hear recently I've gotten an algae bloom. I was wondering if when I did my water changes it would be alright to blow of all the rocks and vacuum the sand. I was also wondering if or how i should go about add more live sand or rock to the tank. Any help would be appreciated.

Thanks