Build Help Plz; panel gaps, Unions, and more

[Aquaman7]

Hello,
After installing the final panel I realized there is a 1/4” gap between panels. I can’t move the other panels closer because the vermiculite pool bottom is complete and the stairs are bolted and cemented into place. I’ve attached a picture. Can I put silicon to fill the gap?
Thanks,
Joe

 

[Aquaman7]

Hello,
I’m installing 2” suction lines from each skimmer. Should I put unions under the skimmers?
Thanks joe