Coral Beta bleaching

I just received a pair of Coral Beta 10Bs. They seem to be in a pretty good condition, but they don't have their fresh original colour. Instead they've become brownish. This must be a frequent problem with coral betas. Has anyone ever tried to bleach them, for instance with a hydrogen peroxide solution?
The only question is... why would you want to? Fostex banana pulp cones for example do it as a matter of course. It's just part of the natural aging process (that doesn't necessarily mean ageing in a negative sense) of the materials.

You could probably turn them any shade you wanted with watered down food colouring. My own FE126Es, which will be fired up again shortly for testing a new box, were coloured an attractive shade of blue by DaveP10 for example.
The cones on Coral units are airdried pulp, never apply anything waterbased on theese cones. They are very sensitive to humidity that´s why the´re so prone to change hue, which, as established in the pass labs thread#5000, is not a bad thing. If You still want to adjust cosmetics use ricepaper-laquer, the kind used for stretching/shrinking rice paper on modelplanes and mix with dry colourpigment of Your choice.
The Corals' ageing process is now inversely proportional to mine. I'd like to invert that. Moreover, one of them has probably spent its life in direct sunlight, whereas the other seems to be of a more photophobic nature. Therefore, one still has its original bright yellow colour (like a marker), the other one is brownish. I wouldn't have any objections if they were of the same colour.