Tough algae removal

[jc555]

I have a filter which I let algae build up on for a long while, a little too long as now I cant get some of it off using a toothbrush. I was just wondering if anyone knew a better way to get this difficult algae off. Im using a hang on the back filter. Thanks

 

[Leeatl]

Put hydrogen peroxide on the algae and let sit for a bit .

 

[jc555]

Put hydrogen peroxide on the algae and let sit for a bit .

Thanks for the response, ill leave hydrogen peroxide on for a bit and see what happens.