new tanks, new fish, crazy husban, can you help

Question
My husband, never been a fish owner, had decided last week that he wanted an aquarium.  I was fine, but asked that he let me do some research and see what our options were.  well when I came home the next day he had bought 2 aquariums; one 5 gallon and one 20 gallon.  he had them set up and I told him that from the research I had done, I had found that you need to wait at least a couple of days after you had the tank set up before you add fish.  that would give me plenty of time to do some research to determine which fish we wanted and the care of the fish.  Well, needless to say, he didn't listen to me.  I came home two days later to find that he had added 3 black fin shark cats (all small), an albino cat, 5 tiger barbs and a suckerfish (sorry can't remember the name of it).  I'm thinking this might be too many fish for this size tank, so I suggested that we move some to the 5 gallon tank.  the next day I come home to make the move and he's bought 2 shubunkins, a black moor AND a calico fantail and put ALL of them in the 5.5 gallon tank.  I'm doing looking up information now and trying to find a bigger tanks for both sets of fish.  I'm new to all of this.  My question is, are the fish that we have together now compatible with each other, meaning, even if I give them a larger tank, am I going to be able to keep them together?  Also The blackfin shark cat, the two smaller ones have gotten small spots on thier bodies.  NOt alot, but still I'm worried about them.

I feel awful for all of these poor little fishies. I want to get the problem solved, get them to a bigger tank and make them all happy.

Answer
Ok, I am going to try to be as nice about this as possible.  EVERY single one of those fish needs to be returned.  Each Goldfish needs AT LEAST 10 gallons each.  For your 4 goldfish, they need a 55 gallon+ tank or a pond.  The 20 gallon can hold no more than 20" of fish.  The black fin sharks need 29 gallons, and should be kept with only one of them...as they mature they will fight to the death.  The albino cat cannot be kept with the blackfin sharks.  The tiger barbs need to be in groups of 6 and in a 30ish gallon tank as they get kinda large.  They also get nippy and aggressive.  The suckerfish is most likely a pleco which gets over a foot long and needs at minimum a 55 gallon tank.  

Another issue is that an aquairum needs to cycle.  this means that as fish poop, it is converted to ammonia, which is toxic to fish.  Eventually, a bacteria colonates the filter and eats the ammonia, and converts it to nitrite.  This nitrite is also lethal to fish.  Another bacteria comes and eats that and converts it to nirate which you remove with WEEKLY 50% water changes.  You really need to get a kit and test the water 2X a day for the first 2 months.  If ammonia goes above .25 and nirtite above .25 or nirate above 10, change 50% of the water.  I suggest taking all fish back and doing a fishless cycle. At the very least, try to get some biospira to add to the filter.  A good place to go to ask questions and chat with fishkeepers is badmanstropicalfish.com  They taught me all that I know.  The spots on the sharks, if they are white could be ich, which needs a treatment of ridick.  This is caused by stress, overcrowding, and poor water quality.  I hate to be the bearer of bad news, but I am guessing that the majority of these fish will die if you do not rehome.  

A good idea for a 20 gallon tank would be a small school (6) of tetras, a gourami or 2 german blue rams as centerpiece fish and oto catfish for your algae control.  Guppies could all be added.  Stay away form the sharks and other large fish.  I would add only 1 or 2 fish at once, and quarentine every fish other than the 2 original ones in the 5 gallon for 4 weeks.  if you have other questions, just let me know.