Maidenhair Fern Aphids

Hey guys. I need some advice. Whenever I get aphids on any other plant, I use some dishsoap lightly dissolved in water and spray them. And Ive always been successful in the past.

But on my Maidenhair Fern, the leaves are so delicate that the dishsoap actually seems to be drying up and destroying the leaves before it can kill the Aphids.

Has anyone dealt with a similar problem and has been successful in eradicating them?

For reference, these aphids are black and the ones I'm used to fighting are usually green.

Pictures attached.

Thanks!