How to add another fan using 25khz pwm-frequency on MEGA 2560?

I 'm using the code below to control a pwm-fan which needs 25khz pwm frequency, it works well.

But now i want to add another fan on pin 7 (same timer used).

How can i do that and use different pwm-values for each pin?

I read about using analogWrite25k(pin, value) but i get errors when i try to use it.

void analogWrite25k(int value)
{
    OCR4C = value;
}



void setup()
{    
    TCCR4A = 0;
    TCCR4B = 0;
    TCNT4  = 0;        
    TCCR4A = _BV(COM4C1)  // non-inverted PWM on ch. C
          | _BV(WGM41);  // mode 10: phase correct PWM, TOP = ICR4
    TCCR4B = _BV(WGM43)   
         | _BV(CS40);   // prescaler = 1
    ICR4   = 320;      // TOP = 320

    // Set the PWM pin as output.
    pinMode( 8, OUTPUT);
}

void loop()
{
    analogWrite25k(80);
    for (;;) ;  // infinite loop
}