The aquarium by meredith mcdonough the discipline needed to cultivate my own thirty gallon sea exasperates even the most patient of my girlfriends. this morning i adjust the wave pump to a gentle speed, appropriate for a cold morning, and turn on the backlight. some of the fish sleep, ghostfully suspended in the water. i track the shimmering paths of the snails across the glass. some have covered large swaths of territory while one has hardly moved, not a good sign. dipping my hand into the water, i worry about introducing bacteria and about upsetting the perfect ph of the water and retrieve the errant snail i've named harpo. i smell him, sensitizing my nose to the subtle bouquet of sickness, some combination yeast, decay, and salt. how is it that the real oceans can withstand almost any abuse while this coddled miniature struggles to live? the coral never holds quite the pink i hope for and fish continue to catch strange sicknesses like the angel fish, greta, who has a parasite. her body has begun to malfunction, her own fins disobeying her wish to go forward. electricity holds this fragile world together. once, the power failed and within days every organism died, rose to the surface and began rotting at a terrible pace, smelling like a crime scene. read this line from the poem: "the coral never holds quite the pink i hope for and fish continue to catch strange sicknesses like the angel fish, greta, who has a parasite." what does the word parasite mean?