This forum seems quiet lately. Goldfish/koi arent usually the best for indoor tanks even large ones as they get big and are very messy eaters produceing lots of waste. Large outdoor ponds are the best way to keep them. You could give it a try, there colorful and active fish. The ug filters can be effective but have to be cleaned (syphon/vacuum]to keep from clogging. They may eat or pull up the plants, don't add a lot until you find out.

Hi
Would certainly agree with the above advice.. If you want to grow plants some good choices for fish are tetras,barbs danios and of course corys.Maybe a pair or two of angels?? Anything but goldfish .lol
There are specialized ways to setup tanks for goldfish that work but require avery different approach ,especially for substrate and filtration.
Good luck with whatever you decide gary