10 Gallon to 55 Gallon Fish Tank?

I would leave the 55 for a week or two to settle down. Depending on how it was moved the cycle may have been disrupted.

If it all settles down quickly and the new fish are healthy, then you could move the fish from the 10 gal in one go. Reason is, 8 small fish (if they are in a 10 gal they must be small) going into an established 55gal will not cause any great upset. No worse than putting 2 fish into a 10gal, and we wouldn't worrry about that.

Then you can use your 10gal as a quarantine tank for any new fish you buy.

Ian

Cycle the 55gal tank first. This should take between 1 and 2 weeks.

provided the fish are all small:

Then introduce half the fish. Wait 2 weeks. Then introduce the remaining fish.

If they are large - only 1 or 2 at a time with 2 weeks inbetween each intro..

I would definately give the new fish, location to get adjusted, 1-2 weeks. Then add in only a few of those other fish before I would add them all. Fish do get stressed, new environment, new food, new water and lightening. Also new sole mates in the tank.

That is a big, big adjustment for someone as fragile as fish. For real.

Your biggest concern would be the health of the new fish. They might have something that your old fish might not be able to handle. Add one of your old fish in with the new fish and wait a couple of weeks. If all is well with the health of your old fish, it will probably be ok to add the rest.

The only thing left to worry about is the possibility that they might outgrow the tank, but if they were all well housed previously, it shouldn't be a problem.

A few at a time would be best, But don't put them in straight away, or not until the temperatures of the tanks are the same. You can try putting a few of them into a clear, plastic bag and letting it float on the surface of the water until the temperature has adjusted.

very little to say after all those wonderful answers...

jus wanted to add... sudden rise n decline in bio load can cause worries to the bacteria colony tht break fish waste (ammonia) into least toxic's like nitrite and nitrate...

make sure u check for ammonia, nitrite and nitrate before introducing any new fish...

often it takes about two weeks for some diseases to show up...

and hence i wouldn't have introduced ANY thing from one tank to the other, including decors, plants, substrate, thermometer

mean while u may also want to have seperate fish nets for both tanks...

I would wait for the tank to get set up and cycle again. Also you should wait for a while so you can observe the other fish and see if they are aggressive or sick.

few at a time would be the best way for introducing

what kind of fish? it would be best to add them both at the same time. visually check them all for disease.

a few at a time