algae ID please

[fishbait]

Can someone please let me know if they think this algae is benefical, benign, or harmful.
Over the last month we have seen a slow increase of algae (green and this red), covering our LR (this is a relatively young tank and we were told to expect this to a degree).
There does seem to be quite a bit of the red stuff now (pictured) and we notice that it even grows on the sand.

• We keep our lights on 12-14 hours a day (is that too much?).
• Use RO water
• 10%water change weekly

PH 8.0, Sal 1.024, Am 0 Nitate 0

Any suggestions?