looking for dry goods

I bought the fiji cube 20 long DIY sump kit and it says i need the things in this pic of the directions, but I can’t find any “acrylic plastic silicone” online in general let alone anything that says it’s safe for aquariums. Any recommendations or ideas as to where i can find it?

Looking for somebody who is willing to sell extra sand they have/want to get rid of for cheaper than retail value ($25/20lb bag). Will probably purchase multiple if it’s worth the price. Would prefer local pick up but willing to pay for shipping If a good deal is made. I have access to the sand...

I have cycled my Lifeguard 14.26 Peninsula. I am now in the process of building my Waterbox X60.2. All I need is one more Prime 16HD , one 3D REEFING shade/diffuser, 2 Nero power heads, and skimmer. I have everything else.