Calcium Carbonate (chalk) or even better (calcium magnesium carbonate) are well known for treating lakes and are probably a far safer option for a lake owner.

I know prevention is better than cure so in looking after our lakes we regularly test nitrate, nitrite, heavy metals and of course ph levels. And if weed looks like its becoming a problem, add a few herbivores i.e. Grass Carp.

I’m afraid my philosophy on this one is; If it’s not broke, don’t fix it! Or get an expert to look at it.

Lee

I have never used lime but it sounds as though it works… but would be worried about what it does to the insect life that you want. Also I have no idea of the price of lime. It would take a 150kg here at La Bletiere and that sounds a lot of lime to go in… and it’s also the “look” after the dosage has gone in, but I suspect it will soon clear.

When we lived in England I kept koi and had a 6000 gallon pond which I used to add salt to in the spring and autumn – this did the same as the lime. In the 6000 gallons I added 20kg of salt and that was enough according to the experts.

The one big advantage the salt has is that it kills all the blanket weed it comes near, but not other plants. It also gives the fish a good clean through.

After about 1 day all the blanket weed in my pond would be in the vortex ready for dumping. Might be useful for any of you that own a pond and maybe one day I will try the lime.

John

Siltex is a proprietry brand of finely ground Calcium Carbonate (chalk) most often prescribed for silt reduction and general improvement of lakes and ponds.

Lime is Calcium Hydroxide most often prescribed for pH control and reduction in phosphate levels and for the reasons introduced above. It will also have an effect on silt. As a stronger alkali it will need more careful handling and dispersion.

My research on liming started with the Siltex recommendations and I then added other comments from fish farmers and French fish vets, so I guess that this will be where my information differs from Siltex.

I’m hoping that we can end up with what we believe to be a common approach to this issue. So far, I’ve found only one thing that everybody seems to agree on – that regular liming is beneficial.

It does appear that satisfactory results can be achieved at a fraction of the cost of Siltex.

David,

The blog provides poor and mis-guided information. For full details and specific use of ‘lime’ you would have been better off providing the link to the U.K’s sole distributor of Siltex.

http://www.ajsfisheries.co.uk where real world use direct from the supplier provides the correct information for this product, unlike whats been posted on the blog.

Having had experience of applying this product and the results, what has been ‘bloged’ is incorrect, hope this helps.

Lime has a very low solubility in water, less than 2g per litre, so when you mix it with water you are making a slurry which disperses through the water column. Whether to use powder or granules depends on how fast the river flows through your lake, if it looks to be fast then use the granules otherwise stick with the powder.