Piranhas have really caught my attention recently and i have a ten gallon tank, is that enough room for one piranha? or is having only one piranha a bad idea?

And wondering if red belly piranhas are even legal in Washington State

No and most likely no. They need at least a 50 gal tank and at least a group of 3.

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SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
http://www.aquariumforum.com/f15/sta...late-3253.html

I agree with Susan, they are schoolin fish and thus should be kept in larger groups (3-5min) I assume. How big do they get?

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35 gallon tank
4 ryukin goldfish (4 - 5 inches)

5.5 Gallon Planted tank
1 halfmoon betta
2 ADFs

Size will depend on the species. I think the smallest is 6 inches.

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SUCCESS IS MEASURED BY YEARS, NOT MONTHS!!!
220 Tank build
http://www.aquariumforum.com/f15/sta...late-3253.html

i would hate to have to clean that tank

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What happens if you get scared half to death, twice?

and don't even get me started about the filtration you MUST has to be at least 3 times the volume of your tank to filter it, as Piranhas are very messy eaters and you cant put any scavengers in the tank so your filter really takes a pounding. Just a thought.

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Red belly's were my first "big" tank back in 77/78. I started with 5 in a 75gl tall. They were silver dollar sized, within a year there were 3 at about 4" (cannibalism). And they didnt attack my hand when i put it in the tank either. The runt had a few chunks out it's back. They were not really to messy, as they ate everything and cleaned fallen debris. I gave them away when they were about 6/7". They are beautiful fish. They definitly need a big tank and need min 3.

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"Buddha in your tank"