That's Gelidiopsis. See page 60 in Algae: A Problem Solver Guide. The blue algae in your other post is on the same page in the same book. It is Hypnea pannosa.
At the risk of being accused of self promotion- the book is a new one I wrote, just published by Ricordea Publishing. You should be able to get it from your local pet shop or via mail order. It has been available for a couple of weeks.
Have a look at the latest issue of Advanced Aquarist Online here on Reefs.org for a review by Doug Robbins.
The red alga #3 you just posted looks like a Lyngbya sp., a filamentous cyanobacteria, but the photo is too fuzzy to be sure- again I refer you to this book!