I've only done hypo once and it was fairly easy and successful. I have a 20 gal QT and only had 3 fish. I started by removing 4 gallons and (slowly)dripping in 4 gallons RO fresh water. Kept repeating process until SG down to 1.009. I started mine during the week when I had to work, so it took me about 3 days doing changes in the morning and at night. Use air tubing with a knot or a gang valve for the slow drip. I was afraid the low SG would affect the fish adversely, but they actually thrived in it. Just make sure you don't bring it down too fast. The ick seemed to disappear when it got down to about 1.011 - 1.010, so I think the 1.009 recommendation might a little safety cushion. Try to keep it at 1.009 for at least 3 weeks, then bring it back up slowly over week #4. Depending on how long you will be away, you may have an issue with evaporation which will increase the SG. Without freshwater top off, my SG went from 1.009 to 1.010 in about 2 days. Do you have someone to add fresh water top off (and to feed your fish)? Hope this helps