Re: purple algae
Looks like cyano. For a young tank it is pretty much expected. Not something you want in your tank in the long run. When you do a water change, siphon out what you can, watch how much you feed for a while and maybe reduce light by an hour or two for a while. How old are your bulbs? Old bulbs can sometimes be the culprit as well, since as a bulb ages it produces a different spectrum than when it was new. Since it is in your 'fuge and display, light spectrum probably is not the issue.
Adding new live rock can also cause a cyano outbreak, as phosphates and other organics can be released from the rock cycling.
Hang in there...it is't very pleasant to look at, but with time, patience and good water quality management it can be beat. It will eventually go away.
Here is one of your pics for those that can't see your photobucket account:
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