how u think you got the root rot dude, what is your water tank temperature? and what is your grow room temperature? i saw you wrote temp went up to 105, that means your tank water also went up, if its higher then a certain degrees it will start causing root rot. you should put your intake with cold air coming in directly hitting your tank to cool down your water further, that is what i did. im using 600w inside cooltube also.
my tank was kept 10 degrees cooler then the grow room, my roots are super white and im growing 3 snowryder autos on 1 5 gallon tank
i also used sesizyme by advanced nutrients the entire grow and that stuff is said to eat up rotten roots and feed new roots the material it decomposes, good stuff u should get some and put 30-60ml in your tank with just water overnight so it can eat up your dead roots, or think about buying some for your next grow