I made a fiberglass over plywood 120 gal in 1970,still swimming,3/8 plate glass. We made 10 tanks over 100,one was 300 i think. Bought casting resin at standard paint store, worked for free at glass shop,got all there cracked store window glass. Used reefer freezer ,coiled hose in freezer,to keep calif water cool enough, outside temp 100 deg valley dude, keept pismo clams,lobster,gorgonian sea fans, horn sharks etc. Best club in high school. We went to da beach lol.
Aloha