The Differences are:
1. Colonial organisms appear as a sphere while Filametous organisms appear as a thread.
2. Colonial organisms is a group of individual organism with a close dependent relationship with other organisms while Filametous organisms form a filametous growth.
3. Colonial organisms form a spherical mass of cells while Filametous organisms form an array of cells with an end to end arrangement
4. Filametous organisms are either sessile or floating while Colonial organisms are generally sessile.