I have done a little work lately reworking my greywater system.
I wanted some sort of biological filtration system, and have been doing a lot of reading on natural gardening and composting.
Which lead me to..... Planting MARSH PLANTS in my utility tub!
That's right, I just put down a couple layers of stone, pebbles, sand, dirt, and plants to filter the water from the laundry before the greywater gets temporarily stored and then used for flushing the toilet.
Here's a video: