Need help with delay

import greenfoot.*;
public class GameBackground extends World
{
    private int score;
    private int starttime;
    private boolean x;
    public void act()
    {
        starttimer();
        lessDelay();
        checkForSpawning();
        //TestOhneDelay(); //später durch starttimer wieder ersetzen
        addScore();
        GameOver();
    }

    public GameBackground()
    {
        super(1500, 800, 1); 
        setBackground("dark-wooden-background-high-resolution-11231.jpg");
        prepare();
    }

    public void starttimer() // 5 Sekunden nach geklicktem Startbutton starten
    {
        starttime++;
        int SpawnDelay = starttime;
        if(starttime == 70 && starttime < 140)
        {
            showText("3", 800, 480);
        }
        if(starttime == 140 && starttime < 210)
        {
            showText("2", 800, 480);
        }
        if(starttime == 210 && starttime < 280)
        {
            showText("1", 800, 480);
        }
        if(starttime == 280 && starttime < 350)
        {
            showText("GO!!!", 800, 480);
        }
        if(starttime == 350)
        {
            showText("", 800, 480);
        }
        if(starttime == 370)
        {}
    }

    public void randomSpawner() // alle ca. 70 ticks/acts soll random ein Käfer iwo am Rand (oben/unten) gespawnt werden
    {

    }

    public void addScore()
    {
        if(Menü.leben > 0 && starttime >= 350)
        {
            score++;
        }
        showText("Score: " + score, 65, 10);
    }

    public void TestOhneDelay()
    {
        if(x == false)
        {
            addObject(new act2(),Greenfoot.getRandomNumber(1500)+ 1, 899); //Nur zum Test ohne verzögerten Start
            x = true;
        }
    }

    public void GameOver()
    {
        if(Menü.leben == 0)
        {
            Greenfoot.setWorld(new GameOver());
        }
    }
    private int delayDelay = 180;
    private int delay = 180;
    private int spawnTimer;
    private void checkForSpawning() // call from act method
    {
        if(starttime >= 370)
        {
            spawnTimer = (spawnTimer+1)%delay; // repeat every 3 seconds (about)
            if (spawnTimer == 0) // at each timer reset
            {
                addObject(new act2(),Greenfoot.getRandomNumber(1500)+ 1, 899);
            }
        }   
    }

    private void lessDelay() // call from act method
    {
        if(starttime >= 500)
        {
            spawnTimer = (spawnTimer+1)%delayDelay; // repeat every 3 seconds (about)
            if (spawnTimer == 0) // at each timer reset
            {
                delay = delay/900;
            }
        }   
    }
    
    /**
     * Prepare the world for the start of the program.
     * That is: create the initial objects and add them to the world.
     */
    private void prepare()
    {
        heart heart = new heart();
        addObject(heart,1351,30);
        heart2 heart2 = new heart2();
        addObject(heart2,1409,37);
        heart2.setLocation(1404,29);
        heart3 heart3 = new heart3();
        addObject(heart3,1465,35);
        heart3.setLocation(1458,29);
    }
}