Size of the Tank

One primary consideration for owning a tank is, of course, how large of an aquarium do I want/need?  Everyone wishes they could go larger.  Who wouldn't want the whole ocean in their home living room?  My wife always jokes that she would like a shark.  Actually she's half joking, she would like to have a shark but we just don't have room for a tank that size.  Obviously, the first consideration in assessing the size of aquarium that you can own is physical space available.  Do you have a whole wall free that you want to use for a tank?  If so...Awesome.  Remember, a tank that size will cost you, plenty.  Budgeting for the tank will be covered in the next post :)   One thing to remember is that small tanks are somewhat limiting. They limit what species of fish that you can keep.  Many fish require a lot of room to swim or else they will get stressed out and get sick.  Change will always take affect on a small system very quickly.  If you have something in the tank that dies that you are not immediately aware of it can cause your nitrates to spike quickly.  If you have a lot of evaporation over a couple of days and you aren't there to top it off, your salinity will swing to a greater extent.  More water simply equals more stability.