Help! Aphid infestation

[Zindaginha]

Hey alls,

I have a greenhouse shelf from Target that has two levels of grow lights on it.

I normally do some kind of watering in the tent every day so it gets regular airflow by being opened up and having stuff moved around, but for the most part it is all set up to go automatically, so when I left town for a week and asked a housemate to look after my houseplant collection, I told her she didn't need to bother with the greenhouse.

Well, I came back today and first thing I noticed was an aphid infestation on one of my kohleria plants!!! It is a sprawling plant and is in a steady growth phase, so leaves are brushing up against other plants.

What can I do about this? I'm hoping to avoid something drastic like neem oil, but I do have hydro peroxide, alcohol, sulpher...

I am beside myself--I've been doing so great with my plant collection, lately!