Will a Siamese algae eater eat small fish? I’d like to get one as well as some lamb chop rasbora (trigonostigma espei). I’m guessing that the rasbora will be pretty tiny when I get them; also, they will only get about 1.5” max. Will they be ok with the the algae eater?
I have had them in the past ( assuming you are talking about the flying fox ,which is what are sold as Siamese algae eaters here, I am aware there are other similar species that go by the same name ). They are good algae eaters but be warned if you don't have a good lid you may come down in the morning to find them dead on the carpet. I thought a water level 6 inches below the rim would keep them in but it didn't.
In answer to your question I never had an issues of them eating other fish and I had some Molly fry in the tank which grew up ok.
my siamese algae eaters are completely peaceful. they don't bother any other fish in the tank. I have two if them (5 years old and 2 months old) and they spend all their time together. I wouldn't worry about them eating any other fish in your tank
As mentioned, be careful when buying, too often LFSs label incorrectly. I have kept SAEs with many different small fish including rasbora. In fact they have shared tanks with my breeding pairs of Bolivians and EBA, and they have never eaten the fry.
They do help with the algae when young, but... as they get older they do eat less of it. I would keep at least a pair if not a trio. They enjoy playing tag. Just remember they are like torpedoes with jet packs. Zoom Zoom.