Once I get moved, I'll probably order the new fish online just to get it taken care of.
A python is the single most important part of any aquarium. I would have given up the hobby 20 years ago if I hadn't discovered the thing.
How do you order fish online?
What is a python?
Many of the tropical fish sold in this country come from hobbyists who sell fry to LFS (local fish stores). Once you get a well established species tank, you'll often wind up with far more fry than you want, so you unload them. LFS's will buy them for store credit and sell them to others. There's a website that functions as an eBay for fish breeders, since there's only so much that the LFS will buy. Some guy in Cali (for example) will happily sell 6 very young fish for $20, which is $20 he didn't have before. The LFS would have sold them for $25 each. As the buyer, you'll pay $75 to have them overnighted to you, but you'll still come out way ahead than if you'd purchased them locally. Since I can't go to Venezuela to get the fish I want, this is the next best option.
A python's a 25' hose that connects to a kitchen or bathroom sink. It'll drain water out of the tank very quickly, and then by turning the valve, it'll pump water back into it. You can replace 50% of a 50 gallon tank in about 5 minutes with very little fuss.