I think finding alternatives to liverock would be beneficial. It's all "mostly dead" rock anyways, if you think about it. How much of the living things survive when it finally reaches our tanks? like 10%? Often the rock's left to bask in the sun on the beach until the locals gather it all up at the end of the day.
Public aquariums usually used the fossilized coral dug up in ontario. No impact on the reefs, and much cheaper.
As hobbyists, we could try to buy used rock whenever possible, even though it's hard to find, and cook it if needed.
Also, if the collection and shipping techniques were improved vastly, where the rock collected is 90% alive instead of 10% alive when it hits our tanks, we could buy much less of it, and instead seed various forms of base rock with the real "live" rock.
Plus only keeping fraggable coral colonies and trying to buy captive raised corals helps the reef. Look at ellegance coral. It's very hard to keep now because all the easily kept ones have been collected, and now the industry's collecting it from regions of the ocean that it has a hard time surviving outside of. They catch diseases at the holding facilities from all the corals they've never had contact with and consequently often have a very short lifespan.
The funny thing is, the media often cries "they're collecting all the little fishies, the cute doras and nemos are going to dissapear!" I think our gravest impact is on the invertibrate life that's collected for our tanks and the liverock, which acts as the base for life in the ocean.
Let's face it. Even though it's such an enriching hobby, we are a lot more wasteful and have a deeper impact on the world as a whole than somone who simply collects stamps
