I got a portion of chaeto from my LFS and it has these fern-like leaves. Is this some other type of macro algae or is it just how chaeto algae grows? I’m brand new to saltwater and don’t know much about anything.
Yep, that is not Chaetomorpha. It's some kind of feather caulerpa, which I actually prefer over Chaeto for its aesthetics. Caulerpa is probably just as good at nutrient reduction as Chaeto.
It does look like there is some Chaeto mixed in there.
It can be more invasive than chaeto, though. Keep an eye on it, make sure it doesn't get onto any rockwork. It's harder to remove if it's attached to a rock. I would personally keep a pretty low amount of it, so it can't really get its growth going and slurp up all the nutrients. Remember you need to keep some nutrients in the tank, to keep your corals, macros, and beneficial algae alive and growing.
Thank you guys for all of the information. It is in a bare bottom fuge in my sump so not too worried about getting on rock work (once I get my rock in). I have had a little bit of my macro algae get into DT when I was messing with it a little bit because some bits got into return chamber but there’s not enough flow to bring pieces to return chamber on its own so I’ll let them be for now. I’m not expecting much growth or action from it until I get my live rock from KP in anyways because it’s a new tank so not really any nutrients anyways.