Lost on how to control multiple led strips with MEGA

If you replace the function MeteorRain with this does it make a difference?

It basically swaps the outer loops:

void meteorRain( CRGB ColorBackground, CRGB ColorMeteor, byte meteorSize, byte meteorTrailDecay, boolean meteorRandomDecay, int SpeedDelay ) 
{    
    // set background color
    for( uint8_t i=0; i<NUM_STRIPS; i++ )
        fill_solid( grLeds[i], NUM_LEDS_PER_STRIP, ColorBackground );

    for( uint8_t strip=0; strip<NUM_STRIPS; strip++ )
    {
        for(uint8_t i=0; i<NUM_LEDS_PER_STRIP*2; i++ ) 
        {
            // fade color to background color for all LEDs
            for(uint8_t led=0; led<NUM_LEDS_PER_STRIP; led++ ) 
            {
                if( (!meteorRandomDecay) || (random(10) > 5) ) 
                {
                    grLeds[strip][led] = fadeTowardColor( grLeds[strip][led], ColorBackground, meteorTrailDecay ); 
                    
                }//if
            
            }//for

            // draw meteor
            for( uint8_t j=0; j<meteorSize; j++ ) 
            {
                if( ( (i-j) < NUM_LEDS_PER_STRIP) && ((i-j) >= 0) ) 
                {
                    grLeds[strip][i-j] = ColorMeteor;
                
                }//if
            
            }//for
           
            FastLED.show();
            delay( SpeedDelay );
            
        }//for        
        
    }//for
    
}//meteorRain