Not sure how big your tank is but you could try a Rabbitfish, Emeralds didn't work for me either, since i added a rabbitfish, there is a definate decline in the bubble algae, I no longer have to harvest it every 2 weeks.
I don't think it matters what rabbitfish, they all eat algae, small foxface might work., I went with the 2 barred rabbitfish, I've seen him eating it, if you go this route, remove as much as you can manually before you add the fish.
Good Luck!
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