5 day old tank - tiny bubble releases from sand

If this were the Aquatic Plants forum, I'd say you have "pearling." Looks like you're getting diatoms, which seem to thrive in developing tanks. The diatoms are producing oxygen as part of photosynthesis, so you're getting bubbles. The production of bubbles, called pearling by the plant folks, shows that there's a lot of photosynthesis going on.

Are you running all of your lights right now? Keeping them low will help keep algae under control during the cycle.
 
Yes, I'm running all of the lights. Things actually seem to have calmed down so far today. I think you're right about what I've got. I noticed that when the lights are off or the moon lights are on, there are no bubbles being released. When the lights come on, bubbles magically start appearing again. This is also seen on some of my rocks as well.
 
Do I want to be getting rid of the brownish algae stuff that's laying on the sand? It's not getting worse anymore. In fact, it appears that it's starting to slowly break up and float around at the surface, which is casing a little mess.
 
The diatom algae isn't ahuge deal--I'd remove it manually if you can, but it won't cause a problem and many members of a clean up crew will munch on it happily. It might also be causing some of the bubbling, as mogurnda mentioned.
 
I removed some of it last night (before reading your reply today) with the turkey baster. It's a pretty tedious process so I just got some of it out. It doesn't appear to be re-growing itself at this point so I think I'd let the cleanup crew do the work. Speaking of which, when should I be thinking about getting the cleanup crew in the tank?
 
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