I think i may start with the 55 just to be safeA 55 would be a great choice. Or if you want to open yourself up to slightly bigger fish consider going 75g for the extra width. The extra width makes it more fun to decorate as well. With a $500 budget you could make a seriously gorgeous 75g. If you need information setting anything up or sourcing decor like bigger driftwood Id be happy to help you
better safe than sorry for sure, look forward to updatesI think i may start with the 55 just to be safe