50 concrete pyramids were sunk Tuesday about 8 miles off the coast of South Padre Island.

Officials say the structures are part of a project backed by Friends of RGV Reef, to increase fish habitat.

Each pyramid made by Atlantis Marine Habitats LLC, includes cavities to shelter adult snapper.

The structures each weigh three tons, measuring around 10 feet tall.

They were donated and sunken by Lil' Mo Marine Services.