Dont u think it b easier and work better taking the whole thing out of the tank insted of spot treating it? That wont really get the crud out of the pores on the disk.
And you should never mix chemicals like that, you dont know if that could cause a violent reaction, like amonia and bleach
(DISCLAIMER: NEVER MIX BLEACH AND AMONIA OR ANY OTHER HOUSEHOLD CHEMICAL FOR THAT MATTER!)
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