to be honest i do not know if they specifically eat bush algae, but i do know that they will eat practically any type of plant matter, including plants that you put in your tank, so they most likely will eat it. I always throw in some veggies, sometimes zucchini (they even eat the skin), sometimes romaine lettuce, and sometimes leaves from my plants. They eat anything. Heres a giant columbian ramshorn

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I also have 2 golden inca snails that seem to enjoy eating just about anything as much as my ramshorns. Heres a golden inca
