Can I keep a singular piranha in a 20 gallon tank? also what should I feed them. Can I feed them chicken? Shrimp from the grocery? Wild Minnows?
A single Piranha in a tank twice that size is not going to be happy. These are SCHOOLING fish. Without a SCHOOL they are extremely skittish, even to the point of hiding all the time and not eating at all. I know, I know, there are exceptions to everything....Piranha are a fish with specific needs, contrary to what some may say. I have had these fish. Beautiful species. I will not keep them again.
BTW, RBP are illegal to keep in most if not all states...
If you like the LOOK of the Piranha, consider the Silver Dollar (Mylossoma pluriventre), the Mytynnis hypsauchen, or even the Pacu (Colossoma bidens not Colossoma brachipomum).
These all have that heavy built look without the legalities or special diet. They have their own needs granted, (Pacu get huge) but they are easier to keep, trust me, I have the scars to prove it!
JMHO, GL
Let me get this straight ballin, as long as we have proper filtration, change the water using a siphon and after they reach the magic 6" in length, scale back the feeding and you should be good, all justified by saying these are tough fish that can survive bad water.
If these are such the tough fish, than we could apply this fish keeping regimen for other "tough" fish. Arowana, Oscars, Arapaima, RTCs, Giant Gourami...etc,etc. All tough fish, all could be kept alive in a 20g with proper filtration for a time.
You are right, this fish isnt illegal EVERYWHERE, several Piranha species arent considered shoaling and yes, I did mention Pacu on MFK...as a fish that looks similar to a Piranha.
What I was trying to say, however, is that, yes, we could keep said fish in a 20g, but should we? We could keep a Tiger in our livingroom if we feed it on schedule and keep its bed clean, but really? A Piranha in a twenty?
Go for it OP! You should be fine.
Just dont feed it chicken....