You can cut them, just be careful as the dust will bleach any surface or clothing it touches. Please edit your signature so we can see the details about your pool in each post. We need pool size, type, and surface. Pump brand and size, filter brand type, and size, and any water features you may have.
If I remember correctly you have a very small pool and you where going to try and add a pump and filter. Where you able to set it up?