Ponds & Green slime/algae

[pycoed]

I have one pond that suffers badly from green slime/algae & is getting worse each year. Pond is groundwater filled i.e. no flow through it, roughly triangular & holds around 3000 cu.m at a guess. I can't believe this can be good for the water life, which is mainly sticklebacks, minnows & rudd to 3/4lb or so, though mallard don't seem to mind. Lots of damsel/dragon flies & darters plus the usual range of water beetles, shrimps, fleas etc etc. Land around is summer grazed with cattle April - October.
Does anyone have a suitable solution to control this growth without damaging insects & fish life? I have tried barley bales with little to no success, but trying to find small bale barley straw is now next to impossible around here anyway. I've also tried a drag, but the stuff is so "nebulous", its difficult to make progress. Irises/flags are also a problem, but they are amenable to mechanical removal, so are not such a pressing concern, but all suggestions welcome.

 

[Outonthehill]

Try a bale of straw

 

[Derrick Hughes]

Plenty of barley in my yard at Lampeter

 

[Bald Rick]

Better putting barley straw in to horse hay nets then throwing them in on a tether. Gives you more surface area for the algae to cling too rather than a compacted bale

 

[Grandad Pig]

Must be an imbalance in the pond “system”. All to do with the nutrient cycle. How waste products break down, nitrates etc. I have a big man made pond with a pump circulating the water down a stream and back to a filter bed. The stream grows watercress that is cut and composted, removing nitrite from the system. No nutrients no algae growth.

wondering if you have tested the water? Kits are cheap. Could be field run off (cow dung loaded) boosting nutrient levels.

just a thought

 

[pycoed]

Must be an imbalance in the pond “system”. All to do with the nutrient cycle. How waste products break down, nitrates etc. I have a big man made pond with a pump circulating the water down a stream and back to a filter bed. The stream grows watercress that is cut and composted, removing nitrite from the system. No nutrients no algae growth.

wondering if you have tested the water? Kits are cheap. Could be field run off (cow dung loaded) boosting nutrient levels.

just a thought

I've sent for some test kits, so they'll help with the research. How much straw do you reckon would be needed for a pond 70 yds by 40 & triangular(ish)?

 

[Grandad Pig]

The trouble with straw is that it only works whilst the bacteria consume the nutrients. When they inevitably die of the straw adds to the problem (that’s why you must remove it) so only a temporary fix.

sorry not a clue how much straw to add as never used it.

More aquatic plants might help, even more so if you remove them regularly and allow regrowth, thereby removing nutrients from the system. A bit like my watercress. I can only think too many nutrients are getting in the pond from somewhere.

Be interesting to see the Nitrate and Nitrite levels.

Good luck

 

[Bogweevil]

Plant water lilies so that the surface is half covered in summer. Cooler water will limit algae.

You can add a special black dye to shade out algae. Fish etc don't seem to mind.

 

[Highland Mule]

though mallard don't seem to mind

Are you feeding the ducks? Pond around here had owner feeding ducks and killed off the fish as a result. Ducks will transfer a huge load of nutrient into the water.

 

[Gone Shooting]

Can you not divert some land drains into it ? Someone suggested putting a black sheet over the surface - held with 5l containers and block the light hence killing the algae - we cleaned a pool out with yours problems and stocked with carp which helped and increase water flow.

 

[Treg]

Had a neighbour contact me this week wanting Barley straw for this very reason.
Their going to put 20 bales of loose Barley straw into a Christmas tree netting device and place in the water for I think 6 months then need 10 bales every 6 months to maintain enough toxins to kill the algae.

 

[Grandad Pig]

Does Barley Straw Stop Algae Growth in Ponds?

Barley straw is used to stop algae growth in ponds, but does it work? How do you use it to see results and how long does it last? Conditioning barley straw.

www.gardenmyths.com

Worth a read?