I went on vacation for 9 days and had a neighbor feeding my fish a predetermined amount of food each day. Upon my return, the entire tank is fulled with green bubble algae all over the glass, sand and growing vertically off of the rocks. What is the best way to get rid of this stuff. I plan on doing a manual scrub down of the rocks and tank and syphon the sand and doing a 50% water change. Any advice would be helpful....my poor fish.