Cyanobacteria

I seem to be having something of a cyanobacteria outbreak at the moment 

I've had a look on James' Planted Tank which recommends a good fettle followed by a 3-4 day blackout. However, I've also seen some suggestions to use a 3% Hydrogen Peroxide solution which is supposedly pretty instant. This seems pretty risky to me but I thought it was worth checking to see whether anyone else had tried this approach?

Hydrogen peroxide is a source of oxygen. It is an unstable molecule, H₂O₂ and readily decomposes to make water, H₂O and oxygen gas, O₂. Neither of those is harmful, but I don't know if hydrogen peroxide itself is harmful to fish 

Did you come across this in your researches?

Another case of 'do your own research'. 

Hydrogen dioxide is used in the greenhouse and fruit / vegetable industry as a disinfectant.  It can be sprayed directly onto plants, and it kills fungus, algae, bacteria without damaging the plants.  Hydrogen peroxide is too unstable for this use, but it would work if the product would just settle down. 

This product is even used in vegetable field crops, sprayed on the plants, as a sort of pesticide to help control outbreaks of disease.  There is absolutely no residue.

However, plants don't have gills so we still don't know if it is safe for fish.  And the rate that might be effective. 

algae exit works a treat

easycarbo could be used as well just
paint it on affected areas and it will be
killed off 

good pet shop should stock easycarbo in the
plant section its actually a liquid based plant
fertilizer i was told about this by a plant specialist
i am going to by another bottle that tank i have my
co2 dosent suffer from  Cyanobacteria