Cleaning a water feature

[Bogtrotter]

We have a water feature, a drilled stone over a small reservoir, in which the water has turned green and algae have appeared. I bought some Potassium Permanganate, but it has no instructions for use. I've tried the web but all I've found are vague descriptions (a weak solution) or figures which vary between 6.8 grans per 1,000 gallons and 1.25 grams per 1,000 gallons. As I said, it's a verysmall reservoir, but I can probably work it out if I have a definite figure to work with. Thanks in advice for your assistance.

[Buenchico]

The reason you can't find consistent dilution figures on the internet is almost certainly because nobody ever bothers to measure the stuff. Chuck a bit in and see if it works. If it doesn't, chuck a bit more in. Problem solved!

Chris

[rowanwitch]

or use an algae clear solution designed for ornamental ponds but as it is an ornamental feature use it at double strength which would be about two capfulls then run it for a while scrub the srone with it too then change the water

[Wak]

When you do get it cleaned try putting some copper coins or a piece of copper tubing in the water. They will certainly slow down the formation of the algae.

[Bogtrotter]

Thankyou for your helpful suggestions.

[Matheous-2]

Copper sounds like a good tip Wak. May I just add a tip someone gave here in AB some time ago....Don't spend a fiver or more on a bottle of algae 'cleaner'- Use babies sterilisation fluid at 90p a litre or so! Very effective!

[Wak]

I think you should also consider whether the additive is poisonous/harmful or not, as birds will drink from the water feature even if they cannot bathe in it.
5 x 2p coins seems to double the time before the algae appears in my fountain.
Also, the water feeds my fountain through two square holes at the bottom and by putting some soft sponge (washing-up pads?) in the holes the algae is filtered into the pads which are easily removed and cleaned thus extending the time between cleans.
Hope this helps.