Pond surface oily.

[alshookup]

My smallish pond has suddenly got an oily dark film on the surface. My 25 year old Tench has just died and I wonder if there is any connection.

What could be causing the oily look please?

 

[Mmathis]

What kind of pump do you have?

 

[Stephen Noble]

If this is a sudden problem, I would look at what happened to your Tench. Did you find a dead fish and an oily surface? The fish could have decayed and well... You mentioned smallish pond. Don't those fish grow to nearly 3 feet? How many gallons is your pond and do you have any other fish?

 

[brokensword]

the oil will inhibit the oxygenation process and esp in a small pond, that could be a critical factor. I'd try and skim it off or lay newspaper down and it'll stick to the paper, then pull away. Sorry for your loss.

 

[Mmathis]

I assume that you took care of the duckweed problem?

 

[bagsmom]

I will mention that when my small container pond got yucky (I don't know what happened) it developed an oil slick looking film on the surface -- iridescent, rainbow-y looking. No water changes would fix it. There were no mechanical parts in it whatsoever. I think it was something to do with bacteria and decaying matter messing up the water.

 

[yorkshire pudding]

do you have water lillys in your pond ? i sometimes get an oily slick on my wildlife pond when the water lillys start to breakdown.

 

[alshookup]

I assume that you took care of the duckweed problem?

Got nearly all of it out but still got to net a bit more.
thanks

 

[alshookup]

What kind of pump do you have?

Not sure what make or size it is but had for 13 years without a problem.

 

[alshookup]

do you have water lillys in your pond ? i sometimes get an oily slick on my wildlife pond when the water lillys start to breakdown.

There is one fairly small water lilly but I will remove any leaves that look suspect.
thanks

 

[alshookup]

do you have water lillys in your pond ? i sometimes get an oily slick on my wildlife pond when the water lillys start to breakdown.

One small Lilly but I will check it and remove any suspect leaves.
thanks

 

[alshookup]

I will mention that when my small container pond got yucky (I don't know what happened) it developed an oil slick looking film on the surface -- iridescent, rainbow-y looking. No water changes would fix it. There were no mechanical parts in it whatsoever. I think it was something to do with bacteria and decaying matter messing up the water.

Thanks for response, I will watch it closely but I think it is down to decaying vegetation.

 

[alshookup]

the oil will inhibit the oxygenation process and esp in a small pond, that could be a critical factor. I'd try and skim it off or lay newspaper down and it'll stick to the paper, then pull away. Sorry for your loss.

thanks for advice.

 

[alshookup]

If this is a sudden problem, I would look at what happened to your Tench. Did you find a dead fish and an oily surface? The fish could have decayed and well... You mentioned smallish pond. Don't those fish grow to nearly 3 feet? How many gallons is your pond and do you have any other fish?

I have a few goldfish and some Rudd that seem well enough. The large black Tench was found on the lawn about 5 foot from the pond and was barely alive, just slight movement with the gills and body curved. Now dead.No decay on fish or marks where a predator would have had a go at it. I think the pond is about 500 galls.