New Guy

For future reference only post where the post is appropriate, and neither of those are brackish fish so stick to the freshwater forums. Actually what species is the "black fin shark". It might be the brackish shark cat thing. If it is it will way outgrow a 40 gallon and requires at least a 90. Plus it is technically a brackish fish and they need salt while a pleco will die in salt. So if it is the brackish shark cat thing the mix will not work.
 
Sorry if the first part of the post sounded snappy. I don't like common names and get highly confused by more than half of them. This is definetly one of them since the fish has like 4 different common names! So sorry if I seemed nasty I didn't mean it that way.
 
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