gardener1's picture


Observed: 20th August 2012 By: gardener1

Constant problem with algae? in our small garden pond. Bottom of pond is completely covered in green stuff, a lot of which floats to the surface, particularly when it is warm. When taken out of pond (see picture no.2) it is just like a load of green slimy jelly (no shape or strands like blanket weed). Constantly skimming it off the top but it soon returns. Completely emptied pond in spring and within 3 months or so stuff appeared. We've had this pond for 30 years and never had this problem. Any idea what it is and what we can do to get rid of it.


No identification made yet.

Species interactions

No interactions present.


BDeed's picture


Not sure of the species of algae, i would guess it would need microscopic examination. As for the cause it could be due to nitrogen enrichment of the water possibly from plant feed run off? Or may be due to increased levels of sunlight on the pond, perhaps if a nearby bush of shrub which was shading it has been removed?

In truth i suspect there are a variety of reasons (which also include re-filling the pond with tap-water?) as for controls, we have invested in a large number of hungry pond snails and encouraged tadpoles this year which between them seems to have done the trick.


As an aside, Algae should be grouped under plants, if you change it (edit tab) you may get more (and/or Expert help).

gardener1's picture

Our Algae

Many thanks for the comments. We had a tree removed sometime ago and there is much more light getting to the pond now, so that looks like the most likely cause. Will change the location - thanks for the advice.