Green and flowing,

a tide teeming with life.

A blanket of darkness,

a living death-bringer.

A tide teeming with

microscopic cyanobacteria,

a living death-bringer

as your toxic scum decomposes.

Microscopic cyanobacteria

you paint the water green

as your toxic scum decomposes

transforming pond to swamp.

You paint the water green

as you reproduce asexually,

transforming my pond to swamp

with your growing family.

My filter will kill your production

and suck up your blanket of darkness,

to pull this pond back from your swamp

and be clear and flowing once again.