Less expensive methods for the low resolution visualisation of 2D Reaction-Diffusion with boxes?

Less expensive methods for the visualisation of 2D Reaction-Diffusion? Hi, These days, I am writing a 2d reaction-diffusion algorithm by using boxes. I utilised one of the JavaScript tutorials on youtube(Here, https://www.youtube.com/watch?v=BV9ny785UNc&t=1080s ). However, although I transferred these codes to c#, it became a very expensive method because I assigned a simple class to box-shape prefabs and tried to reach their scripts in every frame. The max fps I got is around 20sh. Do you have any idea to improve the performance of this model? (Note: I need to create it with boxes and a grid. Because this is what my assignment is). Thanks in advance….

  void Start()
     {       
 
         for (int i = 0; i < 100; i++)
         {
             for (int j = 0; j < 100; j++)
             {
                 GameObject c = Instantiate(cube, transform.position+new Vector3(i+0.5f, 0.5f,j+0.5f), Quaternion.identity) ;
                 c.GetComponent<CubeMono_scp>().a = 1.0f;
                 c.GetComponent<CubeMono_scp>().b = 0f;
                 currentGrid[i, j] = c;
                 
             }
         }
         nextGrid = currentGrid;
         for (int i = 45; i <55 ; i++)
         {
             for (int j = 45; j < 55; j++)
             {
                 currentGrid[i, j].GetComponent<CubeMono_scp>().a = 1.0f;
                 currentGrid[i, j].GetComponent<CubeMono_scp>().b = 1.0f;                
             }
         }
     }
 
 
     void Update()
     {      
         
         for (int i = 0; i < 100; i++)
         {
             for (int j = 0; j < 100; j++)
             {
                 if ((currentGrid[i, j].GetComponent<CubeMono_scp>().a - currentGrid[i, j].GetComponent<CubeMono_scp>().b)*255 <= 1)
                 {
                     currentGrid[i, j].transform.GetComponent<MeshRenderer>().enabled = true;
                     currentGrid[i, j].transform.GetComponent<BoxCollider>().enabled = true;
                     currentGrid[i, j].transform.GetComponent<MeshRenderer>().material.color = Color.black;
                 }
                 else
                 {
                     currentGrid[i, j].transform.GetComponent<MeshRenderer>().enabled = false;
                     currentGrid[i, j].transform.GetComponent<BoxCollider>().enabled = false;
                     //currentGrid[i, j].transform.GetComponent<MeshRenderer>().material.color = Color.white;
                 }
             }
         }
 
         UpdateGrid();
     }
 
     void UpdateGrid()
     {
         for (int i = 1; i < 99; i++)
         {
             for (int j = 1; j < 99; j++)
             {
                 
                 float currentA = currentGrid[i, j].GetComponent<CubeMono_scp>().a;
                 float currentB = currentGrid[i, j].GetComponent<CubeMono_scp>().b;
 
                 float LabA = 0;
                 LabA += currentGrid[i, j].GetComponent<CubeMono_scp>().a * -1;
                 LabA += currentGrid[i-1, j].GetComponent<CubeMono_scp>().a * 0.2f;
                 LabA += currentGrid[i+1, j].GetComponent<CubeMono_scp>().a * 0.2f;
                 LabA += currentGrid[i, j-1].GetComponent<CubeMono_scp>().a * 0.2f;
                 LabA += currentGrid[i, j+1].GetComponent<CubeMono_scp>().a * 0.2f;
                 LabA += currentGrid[i-1, j-1].GetComponent<CubeMono_scp>().a * 0.05f;
                 LabA += currentGrid[i+1, j-1].GetComponent<CubeMono_scp>().a * 0.05f;
                 LabA += currentGrid[i-1, j+1].GetComponent<CubeMono_scp>().a * 0.05f;
                 LabA += currentGrid[i+1, j+1].GetComponent<CubeMono_scp>().a * 0.05f;
 
                 float LabB = 0;
                 LabB += currentGrid[i, j].GetComponent<CubeMono_scp>().b * -1;
                 LabB += currentGrid[i - 1, j].GetComponent<CubeMono_scp>().b * 0.2f;
                 LabB += currentGrid[i + 1, j].GetComponent<CubeMono_scp>().b * 0.2f;
                 LabB += currentGrid[i, j - 1].GetComponent<CubeMono_scp>().b * 0.2f;
                 LabB += currentGrid[i, j + 1].GetComponent<CubeMono_scp>().b * 0.2f;
                 LabB += currentGrid[i - 1, j - 1].GetComponent<CubeMono_scp>().b * 0.05f;
                 LabB += currentGrid[i + 1, j - 1].GetComponent<CubeMono_scp>().b * 0.05f;
                 LabB += currentGrid[i - 1, j + 1].GetComponent<CubeMono_scp>().b * 0.05f;
                 LabB += currentGrid[i + 1, j + 1].GetComponent<CubeMono_scp>().b * 0.05f;
 
 
                 float nextA = currentA + (dA * LabA - (currentA*currentB*currentB) + f*(1-currentA));
                 float nextB = currentB + (dB * LabB + (currentA * currentB * currentB) - (k+f)* currentB);
 
 
                 nextGrid[i, j].GetComponent<CubeMono_scp>().a = Mathf.Clamp01(nextA);
                 nextGrid[i, j].GetComponent<CubeMono_scp>().b = Mathf.Clamp01(nextB);
                 
             }
         }
         currentGrid = nextGrid;
     }