UK Gallons?

[small fry]

Thanks everyone,
I was starting to get worried, on piranha-fury they talk about how you need much bigger than 75g for 3 let alone 5 , so 5 should do well in there I trust Guppy, or should I go 90g its only six more inches, should I go wider or higher?
also any good shops for tanks its hard to find what your looking for in the classifiedswithout having to travel for days.
any particular filters, heaters ect. I should go for.

 

[DiXoN]

footprint is the key wider and longer is what you want and even by the so called stocking rule some sites adhere too like to rubbish 20g per fish rule 4 piranha in a 48x18x18 is ok.
for piranha an 18'' high tank is probably all you need.