Buying piranhas is quite an investment on both time and money, and should be carefully researched before buying piranhas. The costs of starting a piranha tank depends on where you obtain your supplies from. Buying everything new – which includes a 55 gallon glass tank (minimum), stand, heater, sufficient filtration, and substrate – can easily exceed $1000 – fish not included.
However, if you shop smart then you can cut this cost down significantly. One way is by checking sites like craigslist and obtaining items for less. This should not be used for things like filters, heaters, substrates, tank hoods, ornaments, and other used material which may introduce unwanted effects on your tank, unless they are new.
The other, much preffered way is to buy all your items from Amazon.com:
This is the most convenient way of getting your piranha gear delivered straight to your door not only safely and quickly – you’ll save money on new, brand name items too. Another benefit is that you don’t have to spend time hunting down different items from different places – you can get everything from one place, and pay only one shipping fee.
After you have your piranha tank setup and cycled, now all you need to do is buy piranhas. Below are som sites where you can buy piranhas online:
updating list*

Umm. I have a 150litre tank and I have spaces for hiding and no filter. I am looking for a filter the right size and I have everything I need. I got all that for free! Just need the filter. Is that enough to hold 4-6 Piranhas and where can i get them online?? List still not updated?? Can I hold anything else with the Piranhas?? Like African Ciclids or Minnows?? I also need some sort of Pleco too. Would an Armoured Cat-Fish work??