Semi Hydroponic Roting/fungi

[roguekiller23231]

i'm 70-80% sure it's rot, because there are quite a few dead roots on the top and it's covering them (black patch's that have a 'furry' texture when looked at closely). i've been pulling out a lot of the dead roots and just waiting for it to completely dry out before i try anything else. i suspect the previous owner of the plant kept it wet all the time and never gave it time to dry out.

i'm just a little worried because i don't want it to spread to my other plants and orchids i've got, every time it gets warm i get an almost infestation like plague of gnats! (due to having quite a lot of plants in a small room, and keeping chameleons and other animals that need high humidity).

a sprinkling of cinnamon powder couldn't hurt he plant in any case could it?