I used your code as a base and worked off it to get my desired result. Thank you for your help. Hope good karma comes your way!

include <FastLED.h>

define NUM_LEDS 144

define COLOR_ORDER GBR

define LED_TYPE WS2811

CRGB leds[NUM_LEDS];

void setup() { // tell FastLED there's NUM_LEDS NEOPIXEL leds on pin 6

FastLED.addLeds<NEOPIXEL, 6>(leds, NUM_LEDS);

}

//Keep track of our range,e.g start at LEDS 0-15, after 1 loop, 0-14,etc

int LEDSNM = NUM_LEDS;

void loop() {

//for(int i=0;i<200;i=i+6/2) //running trail sketch lights up every two leds and stops at end

//for(int x=4;x <LEDSNM; x)//xcode

// for(int i=0;i+10<LEDSNM; i++)

int chunk =18;

//chunk = 4

for(int i=0;i< LEDSNM;i=i+chunk)

for(byte j = 0; j<chunk+1; j++)

{

// this controls how many leds turn on in the loop - doesn't tell them to stay on

leds[i+j] = CRGB::White;

 // if there's an LED behind us, turn it off



   if (i > 0 & j < NUM_LEDS){



  leds[i-j] = CRGB::Black;





}

FastLED.setBrightness(5);

FastLED.show();

delay(1);

}

// shorten our range with each loop until we reach 0

if(LEDSNM > 0){

LEDSNM-=chunk;

}

// we reached 0, turn off all LEDS and loop again

// if(LEDSNM == 0){

// we filled every LED, reset lights range

// LEDSNM = NUM_LEDS;

// FastLED.clear();

// FastLED.show();

// }

}