m0useanswered grow question 2 hours ago never heard of coffee being used on aphids.
I would spray your plants with just unscented dish detergent "dawn/palmolive/sunlight" and water, like one teaspoon per L. and then power blast em in the tub after letting it sit for 10 min. most of the aphids will fall off or die in the suds. Can manage the rest by introducing predators or just squishing em. some instant contact killer would be good too. just worry about it lasting on the plants. something with Permethrin would work well. just bud wash em in the end.