Great job guys, I am just not convinced that those habitat balls are the answer? they are costly and so labor intensive heavy to transport and deploy etc. I still think plastic habitat is the way to go and much easier to assemble etc. I foresee those reef balls covered with silt with in a few years
That's an interesting thought that never crossed my mind. They're very sturdy and offer a great rock-like habitat, but they're very heavy and could sink through time if not put in a good, solid place. If they don't sink or get covered by the silt they'll last a lot longer than the plastic habitats.
I don't think there is such thing as the "right answer" for man-made habitats. Plastic and PVC offer a great flexible structure that the fish probably prefer, but it will breakdown and wear over time. These concrete ones are solid and will stay together for years, but they not the preferred structure for fish.
Amberle was talking about some different habitat concepts they were looking into for future plans. They're called Georgia Cubes or Kansas Cubes and consist of PVC and corrugated pipe. Very cheap to buy and extremely easy to assemble and last around 10 years. I don't see a 10 year lifespan on these to be that long, but because of the ease to build and cost, it's a decent ROI.
Here's a video and some pictures of what they look like.