The space is max 36”. I would prefer a tall tank anyway (looks better with tall plants). My budget won’t allow me to get a big tank right now, but I think it’s better to save a few months for the biggest possible tank I can fit in than to get a tiny one right now. I will be keeping an eye open for used tank, but for some reason tall tanks are not very common in Finland. It would be difficult to find a 36” long tank taller than 16” or 18”. I’ll probably have the tank and stand custom made by the same company that made my 55 gallon tank. Then I will order the filter and heater from Germany as they are really expensive in Finnish stores.