1:20 bleach to water will suffice. Don't dip longer than a few seconds and rinse your plants with dechlorinated water until they no longer smell like bleach.
As long as you rinse the plant well and there is no bleach smell then you don't need dechlorinator, I always use it though, I guess its my safety net. I've been bleaching new plants and algae infested plants for over 10 years and I've never once lost a plant. The people that lose plants probably aren't doing it right. They either used to much bleach, left it in the bleach solution to long or didn't rinse it properly, or they lost the plant for some other reason and blamed it on the bleaching.No need for dechlorinator if you have well water, correct?
The Potassium is inexpensive on ebay and it is documented to be a lot easier on plants, bleach is a last resort and some plants will die or so I've read on countless posts and blogs.
Never tried it myself