Images of Aquaculture & Ponds: share for teaching & education

Since creating & teaching many permaculture Impress (LibreOffice's answer to Powerpoint) classes I've collected quite the archive of images related to permaculture. I feel it would behoove our online community to share our images for learning & teaching purposes. All images shared with adherence to & respect for attribution: always telling others the source where you got the image.
We can even use the concept of permaculture zones:
Zone 1: share images that you have taken & created of your projects,
Zone 2: share images that you have taken & created of others' projects,
Zone 3: share images from the Creative Commons, Public Domain, & other other copyleft licenses (eg. the WikiMedia Commons),
Zone 4: share images from permaculture websites, this way they can be attributed & it will hopefully draw more attention to their projects,
Zone 5: share relevant images from any other sources. Fair Use Doctrine may apply in the U.S. (and possibly other countries?) for nonprofit educational use.
Without further ado, I'd like to present what images I've collected so far from my "Aquaculture & Ponds" class. Note, I've not used all of these images in class, I just saved a lot during my research.
Please feel free to upload your critter images to this thread!

More images of ponds: pond garden by PermacultureNews.org, before & after pond by Zach Weiss of Permies.com
If you have any images you'd like to share, please add to the thread. Thanks

Listening to a Bill Mollison permaculture design course & discovered:
Marsilea drummondii edible water clover which can also be used as a green manure, image by Casliber, WikiMedia.org;
...he also mentioned:
flowforms being efficient oxygenator, image from BohemianStoneworks.com

This snippet of a presentation by Zach Weiss (at Wheaton Labs as part of the online permaculture design course) has a lot of lovely images of aquaculture (and fascinating info):