37 gallon tank

  • We are currently upgrading MFK. thanks! -neo
100% agree with convict, no P's are going to be ok in that tank. RBP's do good in shoals anyhow.

Exodons are your best bet I'd say for a piranha-esque fish that will fit in that tank. They love being crowded together so you could fit quite a few in there I'd say.
 
Tiger barbs are a more readily available alternative to exodons too, my group feed like piranhas and are super cheap. Only con is that they tend to pick off the weak ones in the shoal every few months.
 
I normally hate when people post questions and are given grim responses because the general assumption is that more times than not, people don't know how to properly care for their fish. That said however, a piranha really is a very difficult choice. They get large, they're extremely aggressive, and because of these things: the only realistic tankmates would need to be monsters. Meaning you cannot do anything in a 37g setup.

In all honesty, because there's so little you can do with piranhas, I would agree with every post above. Go with something else: afterall we can all offer a ton of options for things you may not even realize are freshwater options.
 
A lone Sanchezi might work, max size of 6 inch iirc?
 
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