I used Fuelmaster Fuel Treatment to get rid of the bug. It is best to try and pump off as much of the "biomass" ( black or brown muck ) that is on the bottom of your fuel tank first.
this saves you a lot of fuel filters and stops the muck going through your fuel system.
One heavy dose of this product cleaned up my problem, and it is not a dangerous product so it doesn't matter how strong you use it. my engine runs far better now than it did before I had the bug, and I put this down to this product cleaning up of the internals of the engine and I also found out that Fuelmaster actually has a "top end" lubricant in it which makes the engine run smoother. another good feature is that it stops the fuel from ageing and stops the build up of gum & varnish, I now use it with every fill up of fuel.