Yeah not sure where you're located but I know tongs in FV carries various sizes of hard tubing. You could cut one to a point and fit it inside your water changing hose so you're poking and siphoning at the same time.
I had insane die off from Vibrant's aquarium cleaner when it came to bubble algae, I had to clean foam covers on my mp40s daily from dead bubble algae. It's in my 100g build thread somewhere.
That being said I'd go manual remove if you can. Every time I use a chemical for something, another nuisance takes it's place.