I had a then 6 inch senegal bite a farlowella literally in half. I've noticed if fish can live for 48 hours with the bichirs (there will be a blood bath with algae eaters) then they leave them alone forever.
Try nerite snails, particularly the zebra (they look like tigers though.) One per 15 gallons and you'll have nary a speck of algae.
How are those snails with plants?
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