it can work well, but with suck a small volume of water you need to choose your plants very carefully. you can strike a ballance but keep in mind that algae is ever present so dont expect to have none, a moderate algal growth is good. I'm not sure where in Qld. you are but at a guess i'd say whitecloud minnows or pacific blue-eyes would be your best bet for mozzie controll.
If you dont want to net the pond use floating plants to hide the fish from view, I use giant duckweed.
Oh & go for miniture lillies or Nymphoides they will flower much better than a stunted larger variety.

Charlie

Thanks Charlie - much appreciated. I'm in Rocky - while it can get down to zero, its usually no lower than about 4 deg C on the worst of our Winter nights, and frosts are extremely rare. Probably more concerned with our phenomenal Summer temps - have to strike the right balance between sunlight and 'boiling' the contents of the water feature.

I will check with the local pet stores to see if they have the species you mentioned - think I need a permit for them too. Will have plenty of time as I need to get the water plants established and I have no prior experience with these 'oddities' :)

Cheers,

Artie

Hi Charlie,
I do recommend going for it--there is so much joy to be gotten from watching little fishies!
I had made lovely pond in my last (rental-sigh!) property, and it wouldn't have had much more volume to it than a half barrel. It was a ripper! I did some net research first (for those cosidering a small pond, just dig a hole, line it with carpet underlay, then put on proper pond plastic, and bob's your uncle). The main thing I'd be worrying about is coating the barrel. Goldfish are just carp, and (as we in Oz know all to well) they'll put up with pretty much anything. However, it would be a bummer if any chemicals in the barrel were poisonous. Best basic bet would be to fill it with water and leave it for, say, three days, then emptly it and fill it again, then repeat (terrible waste of water, but you could put it on the garden.
Maintanence of a small pond is easy. About every month, bucket out about 1/3 to 1/2 of the water (which will get fish poo-y) then refill with fresh water. Your aquarium person will try to convince you to use a water conditioner, but I never bothered, and to no ill effect. Just plop the hose in on slow drizel and let it refill. Mind you that's Melbourne water, if your water is bad, this may not be a good idea...
Once or twice a year (depending on water disgustingness) catch your little fishies and put them in a bucket (takes a long time, think of it as a hunting game), take out your plants, empty out all the water with a bucket (it's disgusting at the bottom, but the compost will adore it), give it a good clean with water only, refill, replant, refish. And remember the goldfish=carp thing. Very resiliant, tho float their prison-bucket in the new water a couple hours to get the temp the same before you toss em in.
Re the mozzies, fish love 'em, so shouldn't be a prob. The best mozzie caching fish are commets, little bugers that cost about $2 each from the pet shop. They're crazy! If your'e feeling sadistic drop in an evil fat green caterpiiar and watch them go! No mozzies for you.
I found the native water lilly the best (the pond was under a gum tree), but in warmer weather and with at least half a day of light a traditional one might work, as long as you've got a couple feet of water.
Good luck! It is the best fun ever--my fish made it through a good few years until a big storm washed in polution from the tree above them (or so me and the aquarium dude decided) and they all died. But the next batch are doing fine, so the new residents tell me.
Cheers,
Emmaline
PS:Thanks for the tahitian lime suggestions, all.

And also, make sure to put in one of those plants you get at the fish shop/pet shop that look like a long strand of sproingy bunches--excellent for airation, which your fish will need. They grow like buggery, so will need a bit of regular ripping back (but again, ace for compost). Your fish dude will tell you which one. And make sure you find the widest barrel possible--a large surface to water volume ratio is best for getting air in.
Cheers,
Em

Mine is a fish-tub not really a plant tub. Having waterlilies and presumably fertilizer there-in will be another consideration as the nutrients will affect the water balance. Mine was one of the concrete look-alike barrels. It sits on the edge of the porch and gets sun pretty much full on. I have a couple of upright bricks supporting a slab of slate under the water, gives the fish somewhere to hide, the water depth seems adequate to stop them stewing (G Coast) in summer.
Emmaline is pretty right with all her tips.
I've not had any mosquito probs, the fish movement seems adequate to discourage them, fresh clean water is the draw-card my the tub-water seems to have reached a good balance.
If you need to seal yours and are concerned about harmful chemicals yes let it age a few days and re-fill a couple of times - syphon it onto the garden. Then set it up again (I DO use chlorine neutralizer) and if still concerned you can usually buy minnow-type feeder fish a few for a dollar to sacrifice, if they survive then others should. Sometimes - well up here =- I know i could catch small fish at a nearby water-reserve that would serve same purpose.

Thanks again for all the great tips people - I had wanted a 'real' pond, but it seems so hard to get the 'natural' balance right. Watching guys in gumboots wading into the pond at the front of our library every couple of months convinced me that I will be better off with a smaller option. The huge waterfall and marshes at Kershaw also seem to suffer from algal buildup, so I guess the only 'cure' is the regular flushing that a real river system gets.

Hi Artie...ponds are not all that much work really....well mine aren't...:) I have a few here, this one is on the back veranda and is by far the easiest one to look after as it's under cover. It is about 10years old and has never been cleaned out, all I ever do is top it up during summer, the clear sheets are great at keeping leaves out yet letting light in. I do have a pump and filter on it though. I have a lot of tall trees so the pond doesn't get as much sun as I would like, but it still does ok. If you are just looking for fish to eat mozzies, and not fish to sit and watch, may I suggest you look for some that are native to your area and are frog friendly...:):):)
{{gwi:2112503}}

Just chiming in with a few thoughts.
Emmaline said she didn't use water conditioners. Salt conditioners are probably unneccesary for a pond. Most pond fish will adapt to whatever is in your pond. Changing your water conditions with conditioners is invaribly more trouble than it's worth. Chlorine/chloramine removers are a different story. Water suppliers add chlorine and/or chloramine to the water supply to kill off microbes. Chlorine also has a detrimental affect on fish. Melbourne municipal water contains relatively low amounts of chlorine so you can get away using it straight from the tap. Check with your water supplier what is being added to YOUR tap water and decide whether chlorine will be a problem. If your tap water is high in chlorine or chloramine I would recommend adding chlorine/chloramine remover (eg sodium thiosulphate) to any tap water going into a pond with fish. Alternatively, if your tap water only contains chlorine, it will naturally dissipate from the water if you leave it to stand for a day before adding it to the pond.

RE: mosquitoes: yes, fish are a great way to remove larvae and give kids/grand kids something to look at. White clouds and pacific blue-eyes are common in the aquarium trade so I doubt permits are needed. If you have access to outdoor power, a pump and a trickle fountain (like in Quenda's pic) will disturb the water surface enough to disuade mozzies laying their egg rafts in the first place. The surface agitation will also oxygenate the water for the fish. A filter can also be hooked up to the pump which will help with water clarity (although they do need maintainance every so often).

RE: plants: please choose them carefully. I'm not an exotic knocker but a lot of exotic aquarium/pond plants are serious weeds. Waterlilies, for example, aren't much of a threat but others eg milfoil, elodia etc are causing nightmares in our wetlands. What makes the problem worse is that garden centres still stock them. Be careful buying plants from aquarium stores as well as many of these plants are much weedier outside of the aquarium than in. I'd recommend tracking down native alternatives. Native milfoils, for example, can be far more attractive than the weedy but commonly sold Myriophyllum aquaticum without the environmental impact.

Andrew