Sorry for asking such basic questions, this is coming from an absolutely newcomer with no knowledge on this whatsoever!
Let's say you want to start a saltwater aquarium, you want to start with a just a couple of fish, but eventually move up to a number you don't yet know. How do you plan ahead to ensure you have a large enough tank to accommodate future growth plans? Assuming a reasonable level of growth without getting too excessive, what is a good size tank to go with? Is it best to start with a smaller tank for the first go around and then work up to one that fits your growth plans, or just go all in at the start and build up?