I have a 30 gallon tank filled with to many fish for the space I have.

I have 3 oscars, 2 african chiclids, and one sucker fish.

I have procured a 55 gallon tank so my fish can move up in life.

What is the proper way to transfer them to the new tank?

And how can I find out how much a 30 gallon tank and 55 gallon tank weight when filled?

I keep all my fish in cans, canned tuna, canned cat food..........

try this site:  
http://freshaquarium.about.com/cs/setop/ht/addfish.htm?terms=light+water

Fill and treat the new tank. Let is sit for several days and then transfer the fish.

Fill your new tank half full and let is set for a few days. This allows all of the chlorine and other junk to disipate. Transfer enough water from your old tank to fill up your new tank. Then transfer fish.

Oscars will get very large in a 50 gal tank, so will the chiclids, these are all very aggressive fish. You will eventuall have trouble in paradise.

Water weighs apx. 8 lbs per gallon.

when i'm going to set up a new tank, i usually wait until i'm going to clean one of the old ones. thet way, i can drain off a lot of the water from the old tank into the new one. clean the old one, and top off the new one with treated water. the old water will establish a mirror of the original ecosystem in a very short time.

let the new tank run for a week, and you'll be able to plop your fish right in with no problems.

P.S.: as a rule of thumb, adult oscars need about 90 gallons PER FISH!! when they get older, they will get territorial and agressive. 90 gal per fish is enough to let them swim and keep them separate.

I understand it's a great idea to take a used filter from your old tank and let it float in your new tank for a while.  It will set up the biological filter much more quickly.

I'm currently cycling a new 10 gallon tank.  I've lost a few fish, but I'm hoping the ammonia and other chemicals will soon stabilize so I can begin to populate it with a few more fish.

I'm also planning a 55 gallon tank after I move to my new place in a few days!  

+1 on the other poster's advice to hit an aquarium forum though.  Arfcommers are experts with advice on guns or wimmenz, but I'd think twice about asking them about keeping fish!

Water weighs about 8 lbs./gallon so a 55 (75 lbs empty) would be the tank plus 440 lbs. 75+440=515
You probably have about 50-75 lbs. substrate (gravel) so 515+75=590 lbs. filled.  The 30 obviously will way less.  Whatever you do, do try to carry a tank when it has a lot of water or substrate in it.

To transfer - scoop out all of the substrate at the bottom of the 30 and put it in the 55.  It has all of the good bacteria in it (assuming you already cycled your 30.)  Syphon off more than half of the 30's water.  Net and transfer your fish.  Syphon off the rest of the 30's water.  Top off the 55 with fresh (declorinated) water of the same temperature and alkalinity for your Africans.  Put the filter system from the 30 on the 55 w/o cleaning it after the crap settles a little and you're good to go.  Depending on where the tanks are located, you may have to make a few trip with a clean trash can for doing the transfer work.  Good luck keeping the fish in one piece.  When they get older they may beat the hell out of each other in a small tank like a 55.  You may want to keep the 30 around as a hospital tank!

Quoted: Fill and treat the new tank. Let is sit for several days and then transfer the fish.

take about 30% of the water from your existing tank and put it in the new tank.  this will speed the process of the tank getting ready, and also make the bacteria in the new water similar to what is in the old water.  also if the two filters are compatible, run the new tank with the old filter.  the idea is to jump start the growth of the nitrifing bacteria.

move the oscars into the new tank, and leave the africans in the 30.  once you have done that, start looking for a BIGGER (yes bigger) tank for the oscars.  they will outgrow the 55 in a few months.  for two oscars you are going to need something in the 100+ gallon range

Quoted: Water weighs about 8 lbs./gallon so a 55 (75 lbs empty) would be the tank plus 440 lbs. 75+440=515 You probably have about 50-75 lbs. substrate (gravel) so 515+75=590 lbs. filled.  The 30 obviously will way less.  Whatever you do, do try to carry a tank when it has a lot of water or substrate in it. To transfer - scoop out all of the substrate at the bottom of the 30 and put it in the 55.  It has all of the good bacteria in it (assuming you already cycled your 30.)  Syphon off more than half of the 30's water.  Net and transfer your fish.  Syphon off the rest of the 30's water.  Top off the 55 with fresh (declorinated) water of the same temperature and alkalinity for your Africans.  Put the filter system from the 30 on the 55 w/o cleaning it after the crap settles a little and you're good to go.  Depending on where the tanks are located, you may have to make a few trip with a clean trash can for doing the transfer work.  Good luck keeping the fish in one piece.  When they get older they may beat the hell out of each other in a small tank like a 55.  You may want to keep the 30 around as a hospital tank!

By clean I would suggest a brand new trash can or bucket that you have only rinsed out with water... NO SOAP!!!

Fillet, bag, freeze.

A 55 gal tank seems barely enough for one oscar sometimes.