GPGPU particle flickering

[monolithMktg]

Here is a fiddle explaining the problem.:
A simple GPGPU particles simulation which begins flickering around the 15-20 seconds mark from its start, gradually builds up and gets worse with time.

I looked online for solutions and tried the following fixes for z-depth fighting:

1. narrowed down near and far planes significantly,
2. turnedalpha onand turned depth off in renderer and set transparency: true in Program settings.

I saw a comment in the GPGPU class which says // to add 0.5 to be center pixel ? but didn't work either when I tried
+ (0.5/this.size):

        // Create coords for output texture
        this.coords = new Float32Array(this.dataLength * 2);
        for (let i = 0; i < this.dataLength; i++) {
            const x = (i % this.size) / this.size + (0.5/this.size); // to add 0.5 to be center pixel ?
            const y = Math.floor(i / this.size) / this.size + (0.5/this.size);
            this.coords.set([x, y ], i * 2);
        }

Any help would be appreciated. Thanks.