depends on the definition of dream
If it was if I was building a house & had unlimited room/money I would do probably a 5-10K gallon tank. Something that could have some reed inhabitants as well as a few triggers/puffers
If it was in my present house my goal is to get a 8x4x3 which I hope to buy in the next year or 2. I think I have it figured out how to plumb things to make h20 changes easier & all that stuff.
The shark tank I installed a week or so ago was 10x5x3 & he plans on turning that into a reef tank when he moves in 3-5 years. Then he claims he wants a 20x20ft x ?? to house his sharks in.