Barrel Pond gone wrong

[LoveDragonflies]

I set up a half barrel pond about a month ago, using a recycled whiskey half barrel from a supplier online. Bought a bunch of plants and put them in at the right heights etc. it looked lovely for a couple of weeks but for the last two weeks or so it’s gone… putrid. Plants mostly dying off. There’s a weird film on top of the water. It stinks so bad it’s unpleasant to be near. I’ve got a bunch of mosquito larvae and those hoverfly maggots that love “polluted water”, which goes to show how bad it is. Has anyone had this problem and how did you resolve it?

You could get this pond guy recommended
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@CuriousQuestioningGal
I got
AISITIN 6.5 W Solar Fountain, Built-in 1500 mAh Battery, Upgraded Solar Pond Pump, Water Pump, Solar Floating Fountain Pump with 6 Fountain Styles for Garden, Bird Bath, Pond and Fish Container : Amazon.co.uk: Garden

I haven't tried it yet, so can't say if it's any better though!

Thank you all, some really helpful suggestions. I will do some water changes and hope that it sorts itself out over the winter months…
If it doesn’t, then I will consider a liner or starting again with a non-whiskey barrel

I did this and had exactly the same, it’s the whiskey leaching out of the barrel. You’ll have to line it. Fish and plants now living happily.

I used a whiskey barrel and did not rinse it or line it. I got it in winter and let it fill with rainwater. I planted it in the spring. It went manky the first summer but it came good the next spring.

This is reassuring, thank you

Hi I’ve got a barrel pond - it’s about 20 years old now !!
when mine has been manky chucking in oxygenating plants 🌱 sorts it out and time !