what's the trick to tell them apart ?I'm pretty sure it is an acropora nana. It could be a valida but I don't think it is.
what's the trick to tell them apart ?
It's all in the coralites. A.nana has long tubular coralites whereas A. nasuta has nariform coralites ( looks like an upside down nose) also, nasuta likes to grow in a table. ( however this is not as good an indicator because it can take on a corymbose or cluster type growth forms as well)
Hope this helps.
So far, nothing, Gon. Should I be worried? I can clear hundreds off the glass daily in the morning if I had to.
I find asterinas to be one of the better detritivores out there. Only very rare forms will eat live coral. When the coral is dead or on the way out, they will consume the dead flesh.
Well, sort of defies what Shimek has reported numerous times. There are one or two forms, which are extremely rare in the hobby, that are a pest. All the rest (I forget how many variants there are but it's a surprisingly large number) are beneficial detritivores.
I've had asterinas forever, in every setup I've had, and never had a single problem with them. They will heavily multiply when nutrients are increasingly available, a sign of something else going on, like a cyano bloom or other sort of problem, and if those problems cause downfall of a coral they will move in and clean up.
If you have the destructive ones, that is really bad luck.