I tried gracilaria and my chaeto might have out-competed it because it slowly all died. You might also try a (legal) caulerpa, they seem to keep up with chaeto better. Has anyone else had this issue?
I have Pom Pom Gracilaria (Gracilaria hayi) from Algae Barn that I'm growing fine next to chaeto.
I can provide some if you'd like, but if you prefer "clean" macroalgae, algaebarn has it in stock.
There's also some sea lettuce in the mix, which I don't think you can avoid getting if you get macroalgae from me. That stuff is growing everywhere in my fuge.
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