*sigh* Too late.. None of the seedlings were very big. Few that were had lost leaves and were tall and spread thin.. I pulled them all, putting the plants themselves in soapy water and the soil in a bucket to hopefully reuse. I killed whatever aphids I saw along the way and I'm scrubbing down the whole area. Now I have to plant out my varieties all over again.
Back in November, a little while after I started the seedlings, I took many of my plants from this past season into the house hoping to keep them alive, but it didn't take long for the aphids that came with them to spread.. and though I sprayed the seedlings with soapy water a few times it was hard to keep a good eye on them between business planning, web development work and a flu that turned into pneumonia (which I'm still fighting)
Have a trick. Outside, aphids never bothered a thing. They were there, but not enough to do any serious damage. Inside, oh damn. So tried to figure out what is different between outside and inside. Put dwarf fig, lemon, and lime in the grow room. They flocked the fruit because it tastes better. Then I can dunk a few plants instead of everything.
Much luck to you. Aphids suck when you are growing indoors.