Need help IDing microscope video

[asylumdown]

I've had a rusty brown 'dust' spreading across my sand recently. It's been there for months in small patches, but it's spread coincides with the addition of some more 'expert' level anthias that are getting fed 6 times a day.

In a few patches, another type of mat that is different shade of true brown, thicker, and produces bubbles has started to form. I put samples of each under my microscope

Here's a video of the rusty dust - unless I've misidentified it completely, I think these are dinoflagellates.
http://youtu.be/EKOfv4UNgb8

This is a video of the thicker, more brown mat:
http://youtu.be/10CcygYORso

Am I right in interpreting that they're both mats of the same species of dino, only the thicker mat (second video) has just grown thick enough to start trapping detritus and that associated microfauna that come with it?

 

[alexander_ktn]

The first shows dinoflagellates, the second one is hard to tell - what I could see was detritus, a foraminiferan, some flagellates etc.

You might not have gotten the "brown mat" causing organisms but the crud beneath it - might be the same flagellates or diatoms.