how long do I need to wait for a 10 gal. fresh water tank to cycle before placing a fish in it?

Any tank that has nothing/no one contributing ammonia and nitrites won't cycle. The whole reason for cycling is to get the pro-bacteria-- the stuff that helps keep the ammonia/nitrites down--to proliferate so they can keep up with the stuff the fish excrete. Any pro-bacteria in the tank (if you've moved stuff from a healthy functioning tank) will die off within 2-3 days if it doesn't have the "food" it needs--that is, ammonia and nitrites. If you haven't been adding ammonia and don't have any little fish in the tank to make a contribution, then your tank is dead by now.

Anyone who keeps any kind of fish should buy water test kits--that ought to just be part of the tank package. Don't buy test strips because there's no way to tell how old they are and the older they get, the more false their results can be. Get the kits (for ammonia and nitrites) that some with chemicals you mix with a sample from the tank.

When you transfer driftwood, old filter media, gravel, other things from an old working tank to your new tank, you should put fish in almost immediately and test the water at least twice daily. If the amm/nit levels show anything (should be zero), do a 25-30% water change. Once the pro-bacteria revs up sufficiently, your tests should show zero measurements of both amm & nit. Then you only have to test the tank weekly or if the fish show any signs of stress.

Your tank is cloudy because the bacteria is blooming. Do a partial water change and test the tank. The rainbows are hearty enough to deal with the cycling process but the oto is more sensitive so leave him in the 5 gal. until the new tank is fully cycled.

I cycle tanks for 4-5 weeks using this method- http://aquatropicalfish.wordpress.com/2009/02/19/f...

It would help if you added the old filter to the new tank, along with the substrate.

Acclimate your fish just like you do when you bring them home from the pet store:

Float them in a bag for about 15 minutes, then introduce some tank water into the bag and wait another 15 minutes(you can repeat this step a few times if you like) and then release them.

I waited 6 weeks for my 20 gallon to cycle, moving gravel, water, filter media from an established tank will speed up the process. But get yourself a water testing kit and keep an eye on the levels. Moving things from an established tank will shave a week or two off.

The cloudy water means there is a "bacteria bloom" and its still cycling, i would wait and get a water testing kit like i said.

With tank jump that small tho from 5-10 gallons you could move everything (water, gravel, filter) from the 5gal to the 10 gal and get away with it i would imagine, and make small water changes every few days until the water levels return to normal

You should be testing the water and watching the ammonia, nitrites and nitrates rise and than drop. Once there is no ammonia and nitrites present its safe to add fish a few at time. You would put them in a bag and float them in the new tank just like you would if you were just bring them home from the fish store.

You need to cycle the tank with a fish. Check out the web sites I have provided

if you test the ph of the water and they are about the same ... and they are the same temp.. temp is a must or you may loose fish .... i just Transfer from a 10 to a 20 gallon i set the 20 gallon up test its ph .. waited for the temp to be a degree or so the same .... it took about an hour or so... cloudy is generally just the minerals in the water and arnt of concern unless your water is dirty

I would recommend to wait for 2 week or till the water clears a bit.

Read my article on Tank cycling.

http://aquariumhomecare.com/modules/AMS/article.ph...

Wait at least 30 minutes and make sure the water you are curently keeping the fish in is about the same temperature as the new tank you will put them in