Originally Posted by herefishy
Read the directions on the bottle.
That's fine if someone already has a bottle of Maracyn Plus in their hands.
I think the question was asked for those of us who are considering the Maracyn series of meds and trying to decide which of those is safe for scaleless fish, such as dojo loaches, for instance, but haven't purchased any, yet.
The antibiotics contained in Maracyn Plus are different than those in the Maracyn and Maracyn Two. Those two I know are safe for invertebrates and scaleless fish because they contain no copper.
But Maracyn Plus contains sulphur based antibiotics, and the question really is, do those contain copper and would that particular Maracyn also be safe for the scaleless fish, or should that one be avoided. It sounds like any antibiotic that is sulphur based might have copper sulfate in it, but maybe not.
The question wasn't how to use it, but should it be used at all when scaleless fish are being treated.
Listings of this product in catalogs often don't give this information, and if it's on the label, one wouldn't know it until after they have ordered it and it has arrived -- in which case, they may only then find out it isn't suitable.
When legitimate questions like this are asked, please refrain from giving flippant answers like in the quote.