Goldfish get too big and too dirty. They also eat plants.
You'll want guppies(they die over winter),gambusa (kinda homely) or rosey reds.
Rosie reds look like mini goldfish and are in scale with a water feature that small. They are heat tolerant and hardy. If you have circulation(20 dollar pump no at the home improvement store) it will drown mosquitos anyway.
You'll have to run the pump over winter in a protected spot with no leaves to overwinter the rosies also. PJ

Here is a link that might be useful: {{gwi:1339577}}

Austin blogger Pam at Digging used a small galvanized cattle trough for a mini-pond. It's not heavy, small pump, and she even has a water lily.

Here is a link that might be useful: Pam/Digging

I've had the "fake" 1/2 whiskey barrel as a container pond for 3 years. You will need a liner for a real whiskey barrel as they leak. Garden Ridge will have them, but not sure if they have the liners. With the plants in, and spilling over the side, plus the plants around the base of the barrel, you don't see much of the container itself, so it really still has "charm". It would be best if you can situate it in a place where it gets some sun if you want plants. Mine gets maybe 3 hours of sun. I have Golden Sweet Flag (Acorus), a standard white rain lily, water lettuce and bloody dock (all in pots) in mine. You can get all of those at HD starting pretty soon. I also threw a few stems of Anacharis (an aquarium plant from any fish store)which just free floats under the water - it's good for oxygenation for the fish. I have 3 fan tail goldfish in mine, which overwinter in a 20 or so gallon tupperware type container in the house. The plants will feed on the dissolved fish waste. I do a 50% water change in mine about twice during the warm months. You will likely get a severe algae bloom soon after you set it up, nasty looking green water for a week or 2, but it will go away by itself as the pond becomes "balanced" and the fish won't mind it. I have a small pump for aeration and the "water sound". The discharge tube just shoots straight up to the surface of the water, just breaking the surface. Most pumps have an adjustment so you can adjust the flow. Set the pump on some bricks so it will not be directly sitting on the bottom of the pond to keep debris that settle on the bottom from getting into the intake.
All my plants survived this winter. I will be removing the plants soon to cut off alot of the roots which have escaped the pots, and also to clean out fallen leaves that have settle on the bottom. Don't want to completely tear it down and clean it, as that upsets the balance and it will take longer to rebalance itself. I like the goldfish because you can really see them hanging out just under the surface. I feed them 3-4 times a week - they get plenty of natural food from the pond. Maybe they will get too big some day for this pond, but it's going to take awhile, so I'll enjoy while they can stay, and find them a bigger home if they get too big for this one. You will really enjoy it - I hope you set one up. Don't get discouraged, be patient, as it takes a couple of months for it to settle in, balance itself, and then, very little maintenance.

My husband put leftover minnows in my water feature then he fed them so much it got pretty dirty. I can't convince him they don't need a handfull of fish food every day, lol. I think I will get some other kind of food like the pellet kind and switch to another kind of fish. I got my real wooden whiskey barrels at walmart last year. I thought they would leak too and drilled a few holes for drainage since I had plants with potting soil in it and the first hard rain I was out there drilling more holes in the sides. It filled all the way up with water and some of my plants drowned.

The half whiskey barrel is bad idea cause tots can fall into them head first and not get out. If you want a water feature it would have to be covered so the kids can't get into it.

You can have one just check out a safe way to put one in.

You're right Barb, tots could fall in. I guess I figure all parents watch their tots, but that's not alway the case. Good that you mention it.

You can be the best parent on earth but kids are kids their fast to do thing's and we are not super moms or dads. Thing's do happen but knowing what you can prevent is good.

I nearly lost my son at the age of 3. We had been out on the boat at Eagle mountain lake and we docked to go sit on the bank to eat. While I was making sandwiches and watching my 2 year old daughter my son and another little girl went to play in the water. Now I thought that the little girls mother was watching them. Well she wasn't watching her daughter cause the little girl came up to me telling me look Robert is swimming. First thing in my head was HE CAN'T SWIM. I ran over to him picked him up..upside down water came rushing out of his month and lungs. Never have I been so scared and NEVER did I take my eyes off the kids when around water, He was wearing a life jacket but he fell face down in shallow water so the life jacket was of no help. There were people all around him too not even paying him any attention that it did not seem right. A child floating in the water.

This goes for not leaving a bucket of mop water alone. Children have drowned in them as well.

goldfish 10 for a dollar are fine their hardy also yes they grow but you don't care you should expect to loose a few you can't beat thst price and the photos are my old place i created that from a pile of dirt and yes used goldfish