Miniature water garden

No matter how often I scrub the inside walls of my aquarium, it usually has a haze of green and red algae growing back. And a school of copepods browsing among the plants.

I usually scrub it all off, just before I take photos. This time, I left things as they were.

Yellow-green and red algae start off with circular spots, becoming splotches. Green-green algae start off as blobs, become bigger blobs. Sand grains (regular fine beach sand) show the comparative sizes.

The copepods have one eye each. The ones carrying a round trailer are females; look closely at the one on the left: you can see the egg cases.

In the sand below, miniature polychaete worms scoot up and down their tunnels, waving twin tentacles to capture today's lunch, bits of detritus, scraps of the algae.

Here, the tentacles extend up into the water column. Food particles travel down a groove to the hungry mouth below.

My flash disturbed the worm and he shrunk back into his tunnel. But he soon forgot about it, and pushed back up to the surface to keep on fishing.

Today, I also saw a two-inch long green ribbon worm, out looking for prey. He's an active predator who likes barnacles. He hid in the sand before I collected the camera.