and i want to hear from you veterans out there about the best way to do it. the current tank is a 30 gallon and i'm moving up to a 55. there are only 6 fish in the current tank. two large Parrot fish 4-5 inches, a large pleco 6-7 inches, a tiger barb, albino catfish and a tetra.
i want to put the new tank in the same spot as the old one my office but i don't know what i should do about the water and the fish and putting them in the new tank. i'm assuming i should put as much as the current water into the new tank to lessen the shock but i'm just looking for some guidance please.

The "easiest" way is to get some plastic totes from Home Depot. I just bought a bunch of 18 gallon totes for $4.00 each. Drain the water from the current tank into the totes and place the fish in the totes.

Move the old tank and set up the new one. The new tank will end up with about 50% new water and 50% aged water. By reusing the old filter media and substrate you will most likely not experience a new cycle.

If you are going to be waiting a few days to make the swap you could even do a partial water change now and keep the old water in a tote with an airstone running. Then when you setup the new tank you can minimize the amount of "new" water that you are using.

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Pretty much what B&U said. I will give the steps I use, but basically just trying to keep as much the same as possible to save stress on the fish.

I would start by doing a water change on the existing tank now. Save the water for use in the bigger tank. If you are using a new bio wheel filter on the new tank, get that going in the changed water as well to start the bacteria going.

Let that go a day or two with an airstone/bubbler and a heater to keep it at the right temp. Drop your fish/plants into the saved water, finish draining the existing tank keeping as much of the water as possible.

Move the tank, set up the new one. All the water you just pulled out goes into the new tank. Add the fish and plants. Top off with the water the fish just came out of.

thanks for the replies, i've never done a water change on any of my tanks, i just add more when it gets low, so how complicated is that to do?

Get a gravel vacuum/syphon from the local fish store or walmart. Probably ten bucks or less. Each week or two you should be performing a partial water change. 10-25% of your tanks volume. Simply start the syphon, run water into a bucket and replace with clean water.

Keep in mind the old water likely has lots of nitrates. It is very good for watering plants.

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