Just a quick point about goldfish, fancy or not, they produce a lot of waste and therefore recommendations are 30 gallon for one fish then 10 gallons extra per additional fish.
The question about goldfish being kept in tropical conditions is under constant debate, some say no - others say yes ............. all agree that they should not be mixed with 'true' tropical fish.
Please bear this in mind when deciding what to do with the large tank as the goldfish must be moved from the 10 gallon as soon as possible.